Same as you would use in a studio if you do this kind of work also.
4:1 ratio on kick and either 4:1 to 5:1 ratio for vocals. Medium attack on kick, slower on vocals, fast release for both. As far as threshold is concerned for vocal I adjust it till the comp starts working on loud/pushed passages only leaving the rest untouched with a little makeup gain. Kick, I like to take off 3 - 6db at most with some makeup gain.
Check out the 'offical live sound' thread just down the list a bit.