When you create your Signiture (which is done by going to your Control Pannel),please bear in mind these few things:

Dont have more than 2 large pictures
Dont have more than 20 lines (this DOESNT include all the colour codes and such)
Dont put rude pictures or language in your Signiture.
Keep it neat
No more than 8 100X100 pics
Dont advertise your site through your Sig.There's this cool thing by your Profile that allows you to put your sites URL there!

Thats it!
PM me if you have questions or need help!