I do most of my shopping in WalMart. A neat trick I've learned for trying on is to garb 2 mens shirts and put a cpl of skirts or slacks between them after ive looked around for a bit, then go to the dressing area. The ladies only look to see how many items you have, not what they are. Once in the changing room, no ones going to see what youre trying on anyway.
Learn your sizes and how the different makers cut their products.
One lady asked me about a bra I had in my basket, and I just told her I messed up one of my wifes in the laundry and had to replace it, she told me that was considerate . lol.
Above all, take a deep breath, act like you know what you are doing, relax, and no one will really care what you are looking at.
Terrilynn