The most efficient way to clean glass is clean it after each use. This does seem like it takes more time, but in the long run, it will keep your glass clean, and will not be a pain in the ass to clean later.
If you have a pipe, banger, or another small glass piece, the Super Soaker is a great way to keep your glass nice and clean.
If you use a cleaner to clean your glass, it is VERY important that you rinse it before use.