I use a small spray gun, an airbrush, and Preval sprayers, depending on what coating and what parts I am coating. http://www.prevalspraygun.com/
The Black Satin (and some others) will cure on the bike, but it is a bit sticky unless you can start the curing with a heat gun, oven, direct sunlight, etc.
The majority of the coatings are rather thick resins. They can be thinned, but go on best when applied thicker with less coats. The Preval Sprayers work just like a spray can, and can be cleaned and reused. Most home Depot, Lowes, or other home supply stores carry them, but they can be hard to locate in the store.