Haley Cairo of Real Simple says backpacks make an ideal beach bag. It has all sorts of dedicated storage space that makes it easy to access what you need.
From the water bottle holster to the back pocket for books or magazines, you can stash your wallet and anything else valuable deep inside the bag and then keep it close at hand.
Stick a cheap collapsible mesh hamper in with your beach gear. Throw in toys, towels, and anything else that needs de-sanding and shake it to get rid of the sand.
Stretch a fitted sheet out as far as possible, and put something heavy, such as a beach bag, in each corner to hold it in place, pulling up the corner around it.
Instead of a fitted sheet, you may prefer to invest in a good beach mat designed to repel sand and water. It also provides more cushioning for lounging.