We need more info, too. Your subject matter is way too broad. What kinds of things are you trying to prove/disprove/count/notice?
On the easy end of the spectrum, you simply ask a group of people (separately) what their favorite color is. They answer. You find out that most people will pick something, rather than not answering, and there will probably be a lot of the same color picked, let’s say it’s red, rather than something more obscure such as taupe. You count and record.
On the more complicated end of the spectrum, maybe you have a group of people read the book Watership Down, and then ask them to recall as many of the rabbit language words that they can (but don’t tell them that you want them to remember these words ahead of time, just have them read the book, and then ask the question). Does it mean that some people pay more attention? Does it mean that some people have a better memory retention? Does it mean that some people have a better propensity for new languages than other people? Does it mean that some people like rabbits and therefore are more likely to remember the words (maybe in the same way that people who like sci-fi are more apt to remember Klingon words).
The type of experiment should be based upon what kinds of things your teacher is wanting you to find out.