Go check out the Transformers thread I made some gif that you might like

Shit's kinda small the size is 115kb

ok cool so for a gif it has to be 150kb got it

It has to be either 400x200 or 750x125 and as a gif it has to be 150kb or less. That's all.

I don't get it

SIGNATURES:
To accomodate standard-sized banners in the signature, including the use of the Zilvia.net banner and Sloganizer.net banners, we are allowing signatures to be one of two sizes. Current users have a signature limit of 400x200px, which is remaining unchanged. The alternative size is 600x125px.
Once 400px width has been exceeded, 125px high is the limit. Yes, that means an image 401x126 will be deleted.
As a thank you to our Premium members, their choice is 400x200 or 750x125, and again, once 400px wide has been exceeded, 125px high is the cap.
The .GIF or total image size limit remains at 150,000 bytes (150kb) according to the .gif's properties tab.
-Jeff

what are the sizes I can use so I can make them into a sig

go look at the gif thread I made something for you hehehe