The classic is to spray a wall, then realize the paint waifted up onto your asphalt roof above the wall. Put a drop on the roof above the wall before you paint.
Use PLENTY of drop cloths, practice painting on something OTHER than your house, and it is better to apply more paint than to wish you hadn't sprayed so much. Make sure you get the underneath edges of the lap siding, buy your paint in 5 gallon cans, and add the second 5er to the first when it is about half gone to keep the variables in the paint more consistent.
If you have a wood sided house, pressure wash the siding first, let it dry, then spot prime the knot holes for cedar tanins before you spray a coat of primer on the whole wall.
Use quality materials. Do not buy your paint from a big box store, instead, go to Sherwin Williams or another pro paint store. (the pros there will help you with more details on how to do this, that is how they make their money. Buy every tool they suggest, it will save you a lot of time. Especially, buy a 3M masking gun, and a Painter's 5-1.
I use S-W Superpaint, which is on sale this weekend, I believe.
Buy a quart of your body and trim colors and paint them on the front of your garage in about a 6 square foot test area to get a good idea of whether you really want to commit to this color. Each 5 gallons of paint will run you somewhere between $100-150.
Tell the guys at the paint store what you're doing and rent the sprayer from them. They will teach you everything you need to know.
Wear a respirator (charcoal filter!) but don't worry about goggles, they are a waste of time. The latex stings the eyes for a minute or two, but it won't blind you or anything.