Going from the left arm to the right tightening in an X pattern (c-bushings) will ensure that the arms are tightened down equally so you don't get a lean problem. So with the axle on the ground, have the ends of the radius arms touching the ground. When you tighten both sides and ever see one arm lift you know they are off from one another. Losen a bit and go to the other side until it rests back down. Once its all tight lift or rock the axle and make sure the ends of the arms lift and touch the ground at the same time for a second check. Make sure its level ground.
As for the frame end just tighten until snug. That nut doesn't need to be very tight otherwise you will loose movement in the suspension. This is why there is a cotter pin there.