The best advice on compression I've seen is 51m0n's wiki posting, which is currently not available due to the continued inability or unwillingness of the site owners to fix the wiki.
Compression is very hit and miss without monitoring. It might work for you, and then again it might not, there doesn't seem to be a lot of science behind it. I've tried Demeter, EBS and Tech 21 and have settled for now on the MXR bass compressor, which does at least have some rudimentary monitoring.
You're probably looking for short attack, 4-8Db compression, soft knee, as long a release as your playing can stand. It always varies though, dependent on the bass you're using, room dynamics, so needs to be set up for every location.
I agree with ProfFrink that it's not a fix for gain issues, but there are some pedals which seem a lot happier with a more consistent and tightly defined signal, the Markbass Synth being one example. That plus your playing needs to be super clean or weird sh*t happens.