Altfish,
This has been my routine so far. I have a 37gal tank. Every week I make sure that I have 6 gallons of RO water in the house from Wal Mart for top offs and changes (yeah, usually that's enough for my tank). I've been doing religious changes once/week with salt mixed water at 10%, and top offs once or twice a week as needed with fresh. Before I do my water changes, I always take out water for testing parameters, I check specific gravity for measuring what I'm putting back into the tank, and I also check temp.
I have just a 4 gal bucket (well, OK, 2). One is for taking water out, because I take water out of the tank after equipment is turned off, take the equipment out to clean, and then replace. Once all of my equipment in the tank is cleaned, I get the bucket of water that's been sitting with salt mixed, measure for what I need to measure for to match what's in the tank and get it as close as humanly possible. When I'm happy with that, I slowly add the new water in to the level that my tank needs.
I did just recently add a protien skimmer, because during one of my recent water changes, I thought the water smelled kinda icky. Tests were all great, but I thought that putting a skimmer in would add to the quality at that point...and it did, tremendously!!!
As a side note, I have actually 4, four gallon buckets available, one for taking water out, one for putting fresh in, and one for acclimation (all very clearly marked). The other one is just for good measure, just in case.
I really hope this helps you...I know it's really confusing at first, but the more you do things, the easier and more fun it gets to be.
Lisa :happyfish