In order to lower the inner portion of the lower control arm when you remove the bolt, the jack will catch the spring tension and then you will let the jack down very slowly. The safety tie down can be anything that prevents the control arm from swinging out away from the car. I didn't use anything on the first side, then after reassembly I realized that the other side would go faster if I pre-positioned the tie down on a solid part of the frame to the ball joint area before removing the inner bolt.
Also, before removing the bolt, put a little upward tension on the inner tie rod mount with the jack. When the control arm is then lowered, the spring tension is very little, and it doesn't seem to stress the other joints/ components enough to do any harm.

Side note: I see that you're from West Virginia - I just got back from Cool Ridge this past weekend. My wife is from there so we went to see her parents. I will be going there again for Thanksgiving, so if you are close you can swing by and I can show you, but it's really not that tough, especially after you do the first side.
Have fun, Adam Bush