Although high-speed blenders, such as the Vitamix and Blendtec, eliminate the need to presoak, soaking is still the best way to acquire a smoother consistency and better all-around emulsion and flavor absorption for milky and creamy end goals.
To soak nuts, place 1 cup of nuts in a quart-sized container and cover completely with water, then cover and refrigerate overnight (8 hours). If you are in a rush, you may fill the container of nuts with hot water, cover, and leave at room temperature for 1 hour. Lemon juice and salt will also accelerate the softening of the nuts, but make sure to adjust the final recipe if it includes those ingredients.