Please do yourself a favor and read up on this subject. This is not something that you can get help with from a forum such as this since there are SO many variables. Sure we can help on a more specific level on each issue, and I am more than willing to give you as much information as I can. Let's try to narrow a few things down:
First, Follow Terry's advice, as it is true and good. Then, you need to find out and arm yourself with some information. I'm assuming that you are on city/community water since you mentioned a meter. Find out the pressure and GPM that you have avaliable. This will determine how many heads you can have watering your lawn per zone. You need to take friction loss into consideration in relation to pipe size. The larger the pipe size, the less the friction loss, and the longer the run, the friction loss increases. If you research this enough you will discover why sprinkler systems start out with large pipe closest to the POC (Point Of Connection) and reduce down to smaller pipe by the time you get to the last sprinkler head farthest from the POC. Each sprinkler head has a different output in GPM (Gallons Per Minute) and all this has to be taken into consideration. Do you see the need for extensive research and why us Irrigation contractors had to study for and pass a rather intensive exam? It really gets interesting when you start doing sports fields and commercial systems.
Oh, and just a quick explanation as to why Terry's advice in PVC to Copper advice is so true and critical: Plastic is more pliable and succeptible to fracture under stress than metal. So when tightened, a female adaptor will tend to expand and crack over time, while a male adaptor will compress and not be subject to that vulnerability.