I don't need to go to the LBS to show me anything.... DH does it for me, as I really cannot remember how to do the straps. I've always worn the same Bell mountain style helmet; I've had several in the past 12 years. In fact, I think it's discontinued now, but there's a slightly newer iteration. Frankly, I haven't tried on any of them, except once, when I went to Belmont Wheelworks, when they were having a sale. I might look at the 2 Murienn recommended. My head is extremely small, so I am limited. I have to buy kid's sized winter hats and glasses.
However, I get indentations and lines from *everything,* so this might just be one more of the weird things that my body does.