I've never ruined anything with static and I never use anti-static spray/wristbands.
Work on a table of good height so you don't bend down much (dining room works) in an uncarpetted room. Touch and hold the faucet of your sink for 2 seconds, it's grounded (connected to pipes underground) which should discharge any static you might have. Do this every now and then. Wear a plain t-shirt (non-wool) and shorts or jeans.
Install the PSU first, make sure it stays off (should be switched off by default) and unplugged. Your video card and motherboard will come in antistatic bags. When attaching the memory and CPU and HSF to your motherboard, have it sitting on top of the antistatic bag. Make sure each of the 4 pins on the HSF are FULLY through, it usually makes a click when it goes through. It will not be easy to push those pins in, you need to apply some pressure. It is recommended that you push the pins in 2 at a time, diagonally, but any way is fine as long as you get them all fully through. This is very important because you need the HSF (and the thermal paste on it's bottom) to be seated tightly against your CPU for optimal heat transfer.
Read the manual about your motherboard. Pop the grate out of the back of your Case, so the motherboard's ports can fit through the hole. Secure the motherboard with screws, and use the color coded grate included with the motherboard to line up with the ports you have sticking out the back.
