My favorite quilting teacher, Judy Hasheider, taught some of us how to make a pillowcase with a cuff in a jiffy -- and nicely finished inside. Here's how it's done:
You will need 3/4 yard fabric for the main body of the pillowcase, and 1/4 yard fabric for the cuff. Square up the cut ends of each piece of fabric (on the grainline). Each piece will be approximately 42" - 44" inches from selvedge to selvedge -- cut them the same length, trimming off the selvedge at the same time.
Lay out the cuff fabric right side up, and lay the body fabric on top of it, matching the cut edges furthest from you. Beginning with the cut edge closest to you, roll or fold the body fabric up in a sausage considerably narrower than the cuff fabric.
Now fold the bottom cut edge of the cuff fabric up over the sausage so you have a three-layer sandwich of cuff, body, cuff: