Let’s say, for whatever reason, you’re the first human ever to make alien contact. Yes, I know, pretty unlikely. Probably isn’t going to be you. That’s a given. But it would be a good idea for us to spare a few minutes and think about it.

Why? Well, for one: Most historians and scientists agree this would be the most important moment in all of human history! In fact, it’s generally accepted that in generations to come, all of history would be divided into “Pre-Contact” and “Post-Contact” eras, instead of the “BC / AD” distinctions we use now. So, to put it one way, you’re going to be the most important person in history. The day you make contact will live on, through all cultures and civilizations, for as long as the human race exists. It will be the defining moment for our entire species. But try not to think about that. You might get nervous and screw something up. Just keep a few key points in your head and try to keep your cool.

First things first: Hold your a$$ still!
The aliens will be quite used to things flailing like crazy and trying to get away. They’ll most likely have picked up a fish or a bird and watched as it flapped like an idiot until it died. They know this is what non self-aware organisms do. Holding still is the first thing you need to do to show them we’re worth our weight in crap. Also, some basic statistics will tell you why you don’t need to panic: Between the insane rate at which technology advances, and the massive amount of time a species must exist to travel through interstellar space, the odds that we will be technologically within 5,000 years of the aliens are roughly absolute zero. Think about it this way: It won’t be “lasers vs. machine guns”, it’ll be more like “nuclear weapons vs. sponges”. The fact that you’re still alive will mean they are going to allow us to exist. Fighting them, Matrix-style, is just not going to happen. Relax and make this count. Don’t panic when you see them. They’re going to look weird, if they have physical bodies at all. They likely won’t look like anything that has ever evolved on Earth. Hold still, be deliberate, and react cautiously.

Next up: Finding a medium to communicate through.
They won’t speak your language, and won’t be able to mess with your thoughts. They might not communicate through sounds, and may not even hear the frequencies we talk through. Human language, with its fickle syntax, won’t do. Feel free to talk, but know that this will just give the aliens a general feel for how we sound. You won’t be able to convey ideas verbally at first. If the aliens seem to respond to visible light, writing things down is your best bet. You can tell whether they respond to visible light by checking out their technology. Is it color-coded in any way? Is it shiny, polished or decorated with text of some kind? If so, great, that makes things easy. If not, they most likely respond to other types of radiation. That’s tougher. You’ll need to use rocks, or other three dimensional objects, to communicate. You should probably bring your own pen. If they provide any kind of writing mechanism, it won’t likely be the familiar cylinder that fits so nicely into our opposable digits.

Algorithms! Do you speak it?
So how can you sum up the last 10,000 years of scientific discovery in a completely universal way? Easy: Math! The aliens won’t know who Pythagoras was, but they’ll sure as heck know his theorem. The right triangle will show our alien visitors, without any doubt, that humans are scientific-minded. Draw a right triangle. I bet that’ll get quite the reaction out of them. Label the sides as shown below. They’ll probably love that.

Forget your pen, or do the aliens only respond to gamma radiation? Well then you’ll need to make do. Got a dollar bill and some coinage? Time to get creative. Fold up a bill as shown below to make a right triangle. Arrange your coins as shown in the last step to prove your mastery of the basics of geometry.

Since the aliens will, let’s face it, probably be major math nerds, they may have things they want to show you. You will probably be hopelessly out of your league. Don’t feel bad; so would Einstein. You might want to let the aliens know that we feel most comfortable in Base-10 math. If you can write, or make marks in sand, something like this might suffice:

Assuming a mastery of high school mathematics, the extraterrestrials will now understand that we’re a Base-10 kinda species, and with any luck, they can begin using our familiar numeral system to talk logic. They might pose questions to you, ranging from describing Pi, to predicting prime numbers, to describing lambda calculus. If you don’t know, immediately repeat some kind of obvious “I have no idea” gesture, so they can tell when you’re in way over your head. I would highly suggest you re-familiarize yourself with basic geometry and algebra now, so you don’t make Earth look dumb by not knowing how to find the diameter of a freekin’ circle if you’re the first person they abduct.

Keep this stuff in mind: They won’t know who Einstein was, but they’ll know about relativity. They won’t call it “Newton’s Laws”, but they’ll know about the conservation of energy. They won’t know the Mona Lisa, but they’ll know hydrogen has one proton. They won’t know our religions, but they’ll know Pi is irrational. They won’t know the name “Darwin”, but they’ll be familiar with natural selection. They’ll be familiar with binary, but it won’t be zeros and ones. If they send you a message with only two characters, repeating, that’s binary. It does not matter which character is our “zero” and which is our “one”. A good universal constant to bring up will be the speed of light, but keep in mind they know what a “meter” or a “second” is. They’ll know mathematical operators, but they won’t know “+”, “-“, “=”, etc. You’ll need to do a few sample math problems for them to catch on.

Great job so far! Now for the end game:
At this point, the aliens will know we’re somewhat intelligent. But let’s face it; you’ve spent a few hours on some kind of alien craft and you want to get home and probably take a shower. Wrapping this up will most likely involve two things: Expressing our desire to learn about them, and acting as their spokesperson for the rest of the world. Draw a simple picture of our Solar System, as shown. It’ll let the visitors know that we understand astronomy. Make an orbit around the third dot from the Sun; that way they’ll know we understand our place. That’s really, really important. And don’t use arrows to point to things; that probably isn’t as intuitive to aliens as it is to us. Conveying that we have discovered our place in the Universe is absolutely key. This will show aliens that we’re curious, scientific, and willing to learn more about the Cosmos. 

And finally, show some daggum humility:
To conclude, you’re going to need to let the aliens know we’ve unearthed our own evolutionary history. Put your personal feelings aside here: Do not look an alien race in the eyes (eyes?) and tell them the universe was created just for us. A good number of scientists believe this might be the “ultimate” cosmic IQ test: The bar by which all alien races measure self-awareness. Do you personally believe that the human race, and only the human race, was crafted by a creator? That’s kewl, but suck it up for ten minutes and draw some kind of evolution chart, showing an increase in complexity resulting in a human being. Don’t fail the cosmic citizenship test for our entire species, okay?

Alright, time to get outta there!
Let’s get you back home so you can take your place in history. The hardest part is over. Now it’s time to get back to civilization, take that shower, and become the most famous human to ever live. You’ll probably be the sole spokesperson for the alien race, so keep this stuff in mind:

1 ) Get dropped off in a major city.
If you’re able, try to direct the extraterrestrials to drop you off in the nearest major city. This’ll be tough, since they won’t know what a mile is, what north or south are, or latitude and longitude. Pointing with your hands is also not your friend here. Try drawing out the local landscape, or coastline, as literally as possible. Tall buildings should be made obvious. They should pick up on this.

2 ) Involve the local news.
Don’t “hold out” until you talk to the President, or someone dumb like that. There are plenty of interested parties (political, military, intelligence) who will absolutely screw you if they get the chance. Make sure every reporter gets your picture, every newspaper knows the visitors are peaceful, and every media outlet knows you as a normal person who got caught up in an extraordinary experience.

3 ) Seriously? No pop culture references.
If you get dropped off in front of a crowd of onlookers, don’t make your first words something like “They’re nothing like E.T.”- Spielberg doesn’t deserve that. Keep your first, immortal words something simple: “They’re peaceful”, or “We’ve made contact”, you know, something that’ll go on a plaque. If you’re dropped off in a foreign country, it doesn’t matter. Someone will write down what you said. Don’t start grunting or attempting to speak the bit of French you learned your freshman year.

4 ) You’ll probably be killed.
Unfortunate. You’ll be the most important human on Earth, and no matter what you do, you’ll be extremely controversial. There are simply too many subversive parties who will want you dead for whatever reason, and they’ll most likely succeed eventually. There isn’t much you can do about this one. Sorry.

5 ) Reproduce as much as possible.
Have a bunch of descendants. If the aliens are big into progeny, they might be designated some kind of ruling race in the future. “Descendants of (insert your name here)” has a good ring to it, don’t you think? Plus it’ll keep your genes alive for a really, really long time. And that’s what it’s all about.

Good luck, and don’t muck this up for us!

[ Source ]