mlm,
Layout your parts and make sure you have what you need before you start cementing them together.
Connect all the pieces of pipe and fittings first, by doing a "dry-run"
If you get confused - you can mark each piece with a marker or piece of tape - numbered in order of assembly.
Doing the "dry-run" first - may eliminate some problems later.
Remember this - when you fit pieces together dry - the dimensions will be a little different than when you assemble them with cement. Normally - I press them together "harder/farther" when cementing them. You want the fittings to "bottom-out" when pressed together. In other words - slide them together as far as they will go. Dry run's normally do not allow them to slide togehter all the way.
Use a good quality PVC cement and PRIMER. Both should carry the NSF rating for potable water service. Most all PVC cements and primers carry this rating - but I've seen some for industrial applications that don't. Look on the lable or ask the plumbing department guy that it's for "potable" water and you'll be fine.
If you have a lot of cuts to make - invest in a PVC handheld pipe cutter. This tool is sweet - and makes it a lot easier to make clean straight cuts of pipe.
Anywhere you want to be able to "disconnect" the piping structure - use a pvc union. These allow you to "break" the assembly, by unscrewing the union, and then reassembling them together later. I use a union on all my pumps as one of the first fittings. This way - I can remove my return pump for maintenance and cleaning - without disturbing all the piping above it.
I like to let the joints dry/cure overnight before running any water through them. It's not necessary - but it allows for a good solid connection - and allows some of the "fumes" to dissipate.
I've never had a leaker yet on a "glued" pvc pipe joint.
