You can do it w/o a spring compressor. Depends on who you ask as to which is the better way. I personally have had a spring compressor break on me while My head was under there. I use a jack to do it. First take the wheel off (obviously). Remove the caliper and support it, set the rotor aside. Remove the tie rod end. Remove the swap bar end lind. Now here you have two options. One you can pop the ball joint (I don't recomend it) or two; you can take the strut bolts (lower 2) off and lower it that way. The strut bolts will most likely be tight so you will need a breaker bar. once the tie rod and end link are off and you have the strut bolts loose, not removed but loose. Place the jack under the end of the control arm (part toward the out side of car) and jacked it up till it touchs and removed the pressure off of the struts bolts. Remove the bolts, step away from the opening for safe measure and SLOWLY lower the jack. IT should not do anything crazy but maybe make a slight pop once you go down so far.
Your going to have to manually remove the spring as it is really long. It will have a tiny bit of tension on it still b/c the stockers are so long but it is not enough to cause it to fly out at you, just watch ur fingers. I find a nice little pry bar, step in the edge/top of the knuckle and pry it out. The lowering springs go in much easier. You still have to do a bit of prying but overall, very easy job.
I have heard of folks using hose clamps to relieve pressure on the spring. I have not done that before.
Disclaimer: This is how I have done this and I am in no way a certified mechanic. So do this at your own risk.