My band is having a section of an upcoming song sound very ska.

Like Reel Big Fish, or fast Sublime stuff.

I was seeing if anyone could help me write a guitar part that wouldn't be to hard.

Mess around with upstrokes and fret mutes on these chords. There's like a bazillion reggae/ska songs based around them.
The below is false.
The above is true.

*world implodes*
Play Bar Chords. On the Up Beat. Mute the Down Beat.


For real though this is the most basic/common way to play fish/ska style guitar.
Use a sharper tone with light or no distortion.
If your going for reel big fish sounds then major key tonality is a good choice.
Check out Streetlight Manifesto for some minor key stuff.
Good luck with this. Post the product please.