Here's the best advice I can give you, although jigs are not my stongest attribute:

1. Use the "appropriate" sized line, preferably fluorocarbon, with the "appropriate" sized jig. In other words, don't throw a 3/4 oz football jig on 8lb line. Do what feels the most comfortable for you that is within the threshold of what works best for line and lure weight.

2. WATCH YOUR LINE!!!!!!! Lots of times, fish will hit the jig on the fall and you'll never feel the strike.

3. If something feels funny or you feel like you have lost contact with the bait, SET THE HOOK! Hooksets are free....

4. Match your equipment accordingly. To me, equipment (rod & reeel) DOES make a difference. Also note the difference between a casting jig and a flipping jig. Casting jigs have light wire hooks and thin weedguards to help aid with hooksets on longer casts. Flipping jigs have heavier-wire hooks and thick weedguards to help the jig come through cover better. The head can make a world of difference as well (ball head, brush head, football head, swim head, etc). Pick the right jig for the depth and presentation you are fishing.

5. Experiment with colors and sizes, rattle vs. no rattle, etc until you get dialed in to what the fish want. Match the weight, skirt (for bulk), and color to get the right falling rate and to make a better profile in the color of water you are fishing (natural colors for clear water, black/blue for muddy water just as some examples).

6. Stay patient. Sometimes the jig bite is ON! When it's not, they won't touch it.

7. Jig fishing is an art (I catch fish, but I have yet to master). Some people are born with it, others excel and make a living from it. Until then, I will practice, practice, practice. It is probably the most complex presentation in fishing.

Whew! That's about all I've got. When in doubt, do what you're most comfortable doing. The crankbait bite and jig bite are closely related. If you don't think so, ask Greg Hackney.