Early season and all season you can use a size 8 or size 10 wooly bugger, black or olive work great. Small clouser minnows work good too. Walleyes it's about the minnow imitation. Use bottom hugging minnow imatation like clousers, muddler minnows and any of the thousands of patterns made to imitate minnow forage. I use clousers the most in the rivers with some sink tip and catch quite a few walleyes in the holes.
There are other times during the middle of summer, when the big mayflies come out on the walleye lakes that you can hammer them on top water or just under the surface.
Good luck.