Tell us about yourself!
one other thing worth mentioning..... At least in the USA, most states REQUIRE by law a backflow valve on the sprinkler system. This is usually only done by a licensed plumber or an irrigation professional which holds a backflow testing license. This backflow valve keeps ground water in your sprinkler and yard from flowing back into the clean drinking water of your home or city. Even a dedicated local well still uses a backflow in most cases. If you dont do this, you could have serious problems. I cant imagine anyone wanting to drink the water from their lawn. Especially if you use fertilizer or chemicals on it for growth enhancement or pest control. Yuck! So, please keep this VERY important point in mind.
There *IS* a reason for 3/4 or 1 inch pvc for the lines. It is called water pressure. Most pro installers wouldnt use anything less than 1 inch for the valves. Period. Reducing to smaller pipe GREATLY limits how many sprinklers you can put on a line. This has to be carefully calculated before the install, otherwise you buried pipe , and oops, not enough pressure for 2 sprinklers..... That would be horrible.