Take a look here...
Here's a pretty detailed explanation of one way to test your pitot and static systems:
http://www.iflyez.com/manometer.shtml
We did this and found it to work well. It's a little trouble to set up the first time, but other builders in your area can use your manometer when you're done. The benefit to this is you can check your pitot system for leaks, your static system for leaks, and your airspeed indicator calibration.
We used one of those blood pressure cuff squeeze bulbs (my nurse wife says it's called a
sphygmomanometer) that we picked up at a medical supply store. It was only a few bucks, and you can apply pressure or vacuum with it by hooking the surgical tubing up to the other end. It's a stretch, but it works. The squeeze bulb lets you carefully control the application and removal of pressure. We figured the few bucks spent there was a lot less costly than screwing up some instruments.
BTW, you're going to have to test the system when it's hooked up to your instruments, or you really haven't tested the system. As cautioned in the other posts, just go slowly--don't add or remove pressure quickly. Take your time, have a helper work with you, and you'll be fine.