Folsom in the month of April is one of the best lake in the northern California. Most anglers are not aware that come April 1 of each year, the lake's inflows are not required to match the lake's outflows, and water storage for summer use begins. This causes the water to fill the lake. During this time of year while pre-fishing anglers can find lots of spotted bass shallow, and from week to week these spots may move deep. Do not worry about the fish moving with the water rising up into the shore line, as anglers can find good action around structure such and rock piles and willow trees. This causes the fish to be at different locations on a day to day basis. The first thing I would do is rip a Lucky Craft ripbait (Stay-See 90 ,Ghost or Dobyns color) or throw a Zoom Fluke, or event try some top water offerings like a Spook or Vixen. Have your partner do something different to figure out what the fish are wanting. As the sun comes up I would use a 4" Green pumpkin or Watermelon Red Flake Lizard on a Carolina rig off points. Then when you come to flooded willows I would throw a wacky rig Senko - Cinnamon purple with a #2/0 Gamakatsu circle wacky hook with weed guard (see picture from last year success). I would also have a 3/8 Capt Jack Jig tied up in green pumpkin with a Yamamoto trailer. Also would also look in the shallows as there may be some fish getting ready to spawn. Cover a lot of water until you find a pattern, and then try that pattern on different locations throughout the lake.
Good luck Future Pros!
Andrew Sayles
California BASS Federation Nation, President