Find the weeds boulders and channels fish the edges.There has to be a drop off to the main lake???If there is a river coming in hit that bay late March fish will be getting ready to spawn.2' off the bottom in 2'-15' of water, @15' bring bait up more.Use a sounder try moving it back & fourth drop it down ,do the same you should be able to tell where the top of the weedbeds are.