"Wow, guess all those stereotypes was right, come on guys, your better than that aren't you?"
The easiest way to communicate with aliens is this:
First, put out dots with numbers next to them, for example, ... 3 .... 4 .....5
Do this up to the point where you can demonstrate that we have a Base 10 mathematical system. Going up to 25 should be enough for them to get the Idea.
And then, do a sum like 5^2 = 25, and a few more basic sums.
And then show them Pythagoras. Us knowing Pythagoras proves that we have at least some intelligence. You can go further and show them other things like Pi.
These things work because they are constant across the universe. Any other somewhat intelligent species, no matter the language, and no matter how strange the planet they come from, will understand the same maths, because no matter where you are in the Universe, Pi is always 3.14....
Well, Some of us are intelligent. Just gota hope the first person to meet aliens knows basic maths.