It's really the same as installing any screen protector on any device. The shower/steam idea always helps to reduce the amount of dust in the air. A liquid such as what Zagg uses for its installs can help as it prevent the screen protector's adhesive from immediately sticking, giving you some time to adjust the placement of the screen protector. If you don't have solution handy you can mix a tiny amount of soap with water or use Windex. I can't guarantee that the liquid application method will work with all screen protectors do do so at your own risk if not instructed by the manufacturer.
All screen protectors require a clean environment, clean supplies, clean hands and, most of all, patience. You can avoid bubbles by carefully applying the screen protector with a smooth motion. Squeegee out the remaining bubble but make sure you're not using something that will scratch the screen protector as a squeegee. Some small bubble may work out with time. Experience and practice help. I've applied many and if definitely gets easier as you go.