The hip pop described could be any number of things... most relatively harmless. Be careful... get it checked by an MD if it continues/worries
Top of my list would probably be rubbing of soft tissue, (ie ligaments) over the femur bone causing the popping. Or could be Tensor Fascia Latae, or a cartiledge or bursa issues any or all of which combined could contribute
There are a number of exercises wheich can stretch out that area. Laying on the edge of a table lying on your side, both legs straight. Take the top leg and keeping it straight, let it hang off the edge of the table (without holding it up) Then staying on that table switch sides of it so you can hang the same leg over the edge in the opposite direction (once behind you, once in front of you, over the edge of the table)
Hopefully others will chime in...