Originally Posted by DanaMac
Learn hands-on from someone else before you just jump into it. You can't just read a book or website and expect to know everything about installing/repairing/servicing sprinkler systems.
Amen to that, but if you can't learn hands-on from someone else, then learn whatever you can from the books. If you're in a state that requires you to take an exam and to be licensed before doing business, then hit the books... and I mean big time. Then, when you are worried about getting hands on experience, do as Mark with Green Monster did. Install your own system, or help a friend with his. Learn from your mistakes, then crawl before you walk.
By the way, never stop learning. The more I learn, the more I learn that there is still a lot that I don't know.