Your guide to soaking nuts, grains, and legumes.
Soak raw nuts or seeds for at least 4 hours but up to overnight. Drain and rinse. You can either eat them right away or make a lot at one time and dehydrate them in a dehydrator or the oven at 300. In the oven, place them on parchment paper and stir occasionally until they are dry--this takes several hours. Things like flax, chia, and hemp hearts should not be dehydrated in the oven, as they contain volatile oils and need to be dehydrated at a very low temparature.
Soak whole grains overnight or up to 24 hours with a water change at 12 hours. Drain, rinse, and cook. They typically need 3/4 the amount of water that unsoaked grains would require to cook.
Lentils absorb a lot of water very quickly, so make sure you give them several inches of extra water. Soak them for 12-24 hours, with a water change at 12 hours. Rinse, drain, and cook until soft.
Soak for at least 36 hours or up to 4 days, with water changes every 8-12 hours, increasing in frequency as time goes on. If you start seeing little sprout tails they are done, no matter how long they've been soaking. This will happen faster in warm weather.