I use PoolMath every day - it's super simple, and helps you keep track of what you need to add, and more importantly, what you don't.
#1 - if you dont have a good
test kit, get one now. It's basically essential. Knowing what your current chemical status is is vital to keeping stuff in balance.
#2 - Read the
basics - get an idea on how we do things. It is NOT the way the pool store does it
#3 - Feel free to ask questions, it's what we do around here.
#4 - seriously...get the test kit - best decision you'll make (other than coming to TFP!!)
Pool Math is super easy. Basically install it on your phone/tablet etc, and then follow the steps to setup a 'pool', set the size, type etc. Once done, you simply log your test results, and it will show you what you should add to get to where you would like to be. Here's a snapshot from mine - you can see where my last set of test results are shown, and suggestions on what I should look at (for me, the pH, TA and CYA numbers are something I already know about and I'm comfortable with). Theres a way you can link them to this site too, so the experts can even look at your logs without you having to copy/paste them (not sure I've figured that much out yet).
Clicking/tapping on one of those tiles then shows you what you might want to consider doing to resolve that 'issue', automagically calculated based on your pool specifications.
