Wearing a backpack is uncomfortable for me, so last summer I bought a micro-fiber "healthy-back bag" from the LL Bean outlet. I can wear it over my shoulder like my purse, but it has a padded shoulder strap, lots of pockets on the inside and outside ... even a place to carry a 16 oz water bottle.
I was able to fit 3 ponchos (folded in a ziplock bag), my camera, a mini-umbrella and two 5x7 CM albums for collecting autographs.
I also wore a small fanny pack to carry my checkbook/wallet and KTTW in, even though there was room in my bag for them I found it more convenient to have them in a fanny pack.
HTH, Cheryl