I've never soaked them. I do water them however.

I save mine from year to year, keep them totally dry in paper bags in cool place. I just pot them up (4" plastic) in any potting mix and water well, they will sprout pretty quickly, then I plant them out once they are pretty well along. You can soak them if they are going to go into a fairly dry medium and not get a lot of water.

I bought all red this year instead of the mixed colors already growing. I dug mine up before and then accidentally rotted them....this year I'll try the paper bag strategy. Thanks for the help.

I soak mine briefly, but consider it optional. Once I left them in water too long and they turned to mush, so now I err on the side of caution! The key is to not let them rot, so whether or not you soak them, water the soil they're planted in very lightly -- just enough to be barely moist. A well-draining medium is ideal, so if you have any cactus/succulent mix, that would work well.