I used this tutorial as a starting point, changing the dimensions and the pattern to suit me. (I started with a flat piece 13.5″ x 26.5″, yielding a bag 10″ x 11.5″ x 3″.) I also increased the length of the handles to 22″, and used only a single layer of interfacing, 1″ wide, instead of the 4 layers you end up with following the tutorial.
I didn’t add any pockets to the tote, but I did make a little pouch with a snap closure to go inside, just big enough to hold scissors, thread, a seam ripper, and any other little tools I might need for a hand sewing project.
I’m currently working on a slightly more ambitious beach tote with pockets and some fancy touches, but it’s slow going with a newborn in the house!