There is a trick we're taught in school regarding that question. Look at this sentence: The teacher wants to talk to you and me. We're tempted to say 'you and I' because most of the time that is correct, but take out the second person and look at it again. The teacher wants to talk to me. The teacher wants to talk to I. Which one looks correct? The first one, right? It works the other way around, too. You and I will go. Which looks correct, I will go, or me will go? If you want to be flawless, use that trick, but honestly, people aren't really going to notice if you say it wrong. Native speakers (including myself) do it all the time, so don't worry too much about it.

As a rule of thumb, use "You and I" when it begins a sentence and "you and me" when it ends the sentence. Examples: - You and I are in love with the same girl. - She loves you and me (or me and you). When in doubt, do as Maddie suggested: remove the second person ("you") from the sentence and see if it reads correctly: - I am in love with the same girl. - She loves me.

When you are writing the rule applies, but when you are speaking, feel free to use both

you and i is a correct form, but you and me sounds better.