A/C problems

So I broke down and took my 04 to a shop to diagnose what was wrong/where my A/C system was leaking. They told me there is a leak in the compressor and the condenser. I was quoted $1,169.99 to fix everything. There is no way I am ever going to pay that much. So here I am. I plan to order the condenser/dryer and compressor off rock auto and replace it myself, but I would like to know what steps I should do it in, and I don't want to forget to do anything. Odds are I will take it to another shop to have the system flushed, vacuumed, and refilled with refrigerant. But everything else is on me. So what am I going to need to do?

Thanks