How to capture personality..?

[Lyra Heartstrings]

Alright, so, a good friend of mine asked me to do the writing for a game he is coding. I agreed to. There will be a PvP mode and a story mode. I'll be doing the general writing for both.
I'm doing the "Start Match" lines for PvP right now. So far, I think I'm doing okay. However, I'd like some tips. The characters are all from MLP, so they obviously have personalities. I'm just wondering how to capture it.
If you want to know what I'm writing for:
Twilight Sparkle (http://mlp.wikia.com/wiki/Twilight_Sparkle)
Applejack (http://mlp.wikia.com/wiki/Applejack)
Fluttershy (http://mlp.wikia.com/wiki/Fluttershy)
Rainbow Dash (http://mlp.wikia.com/wiki/Rainbow_Dash)
Pinkie Pie (http://mlp.wikia.com/wiki/Pinkie_Pie)
Rarity (http://mlp.wikia.com/wiki/Rarity)
Any tip will help. Thanks guys!

[GummyUnicornDerp]

Twilight Sparkle - She's a nerdy, yet capable character. She can do anything she puts her mind to, but she is very invested in her studies and fixing everything. EVERYTHING.
Applejack - I refuse on this pony. She is my least favorite, so yea. She is a southern, nice pony.
Fluttershy - She's an adorable, shy pegasus. She did get angry in a few episodes though.
Rainbow Dash - She's a spastic fluttershy. She's not shy at all and very excitable. She also has the gay pride rainbow on her butt, so she's amazing. Wait, is it the right colors? Whatever.
Pinkie Pie - OH MY GOSH, OHMYGOSH,OHMYGOSH,OHMYGOSH. That is all.
Rarity - I don't even remember.

[Lyra Heartstrings]

Twilight Sparkle - She's a nerdy, yet capable character. She can do anything she puts her mind to, but she is very invested in her studies and fixing everything. EVERYTHING.
Applejack - I refuse on this pony. She is my least favorite, so yea. She is a southern, nice pony.
Fluttershy - She's an adorable, shy pegasus. She did get angry in a few episodes though.
Rainbow Dash - She's a spastic fluttershy. She's not shy at all and very excitable. She also has the gay pride rainbow on her butt, so she's amazing. Wait, is it the right colors? Whatever.
Pinkie Pie - OH MY GOSH, OHMYGOSH,OHMYGOSH,OHMYGOSH. That is all.
Rarity - I don't even remember.

I got Fluttershy COMPLETELY finished, no editing needed. Rainbow..I'll be editing. Pinkie, I'll edit, aswell. The others I haven't even tackled. It sucks. x_x

[GummyUnicornDerp]

Pinkie is amazing. You have a hard task ahead.

[Steve Jobs]

erhmagerd ponies. That is all :P