Rendezvous Beach at the southernmost end of the lake has is your best bet for nice camping and a nice beach. It also has trees and shade, unlike the camping on the east side of the lake. There's also a KOA in Garden City, just north of the Logan canyon road. There are many spots to pull onto the beach and lauch your cat, depending on if you have a 4x4 and the water level, such just south of the Ideal Beach Resort (near Rendezvous Beach) or just north of the ID border at the Bear Lake West beach.

I'll be up in Fish Haven on the ID side starting next weekend (about 7/15). Our cabin is right at the Fish Haven sign--stop by and say hello if you want to sail.

Photo of Bear Lake attached--note the Carribean colored water!