I've learned that sometimes a great joke is made from that first smart ass remark you make. That quick unfiltered, unedited quip can be soulfully cutting and down to it.
For your comedy writing sake I advise you become aware of that and capture those spews.
An exercise I like to do is flip thru cable stations and make a smart ass remark about any station's programming I land on. I just go with my funny gut and have fun. I spit something out, first impression stuff no editing just go go go.