Some writing help, maybe?

Hello you guys,
since we have some talented guys here in the forum,
and I am creating a little game with my limited english... "knowledge".
I wanted to ask if someone can help me with some tips
in creating more character types.
Currently trying to give characters more personality,
since until now they all sounded the same...
Though I am not sure where I should even start,
so if you guys got some good ideas I would be happy to take
anything I can.
If some of you like to correct bad english, wouldn't mind
some one to look over my stuff...

If this is in the wrong section please tell me or just move it,
wasn't too sure where I should put this.

*someone

An very late answer, but I hope it'll still help.
Maybe you could tell us what kind of game you're working on (i mean what kind of universe) and also what kind of characters you aim to create.
Are they heroines? Villainesses? Something like both?
Do they have specific powers or appearances?
Developing a character from basic indications about them looks fun to me, so maybe I could give you more clues if you give me more infos.
Also you should try writing a (short?) backstory for each of your characters, that should help.