English isn't my native language and I'm not sure how to best use contractions in my game. I have decided not to use slang because it would just make it harder for me. I try to stick with the "rules" but in this case I'm not sure what the rules are. I have considered not using any contractions at all but that seems to make dialogs a bit clumsy and not as fluent so I'm pretty sure that I want to use at least some contractions.
Which contractions should I use? I have found many lists but they all contain a different set of contractions.
Is it weird to using some contractions but not others? If I use contractions such as I'm, he's and you're would it be weird not to use he'd, you'll and we've?
How important is it to be consistent? If I use a contraction once should I make sure to use it consistently everywhere?
In which situations should contractions be avoided? I know that contractions are seldom used at the end of sentences (e.g. I'm older than you're). The two words also need to belong together (e.g. the socks that I gave you're blue). Are there more?
Is there a difference in the use of contractions between British English and American English?