Like hairball said, get a few different colors, sizes, and brands and start fishing. You will eventually get some confidence in a couple of different jerkbaits and then begin to expand your arsenal based on your preferences.

For me, I definitely think that clearer water is better because jerkbaits don't create a huge commotion so they attract more of a visual bite. As far as colors, when the water is really clear, I prefer a shad pattern that is translucent. As the water gets slightly more colored, I like a shad pattern that gives off some flash. When the water is stained, I'll throw one that is darker in color like an orange, gold, or green that also gives off a lot of flash. As far as depth goes, it just depends on where the fish are. I've caught fish on deep diving X-Raps and I've caught fish on floating jerkbaits as well. Learning a new technique is a lot of trial and error so just don't give up. Good luck!