Fun! Quite fast!
I watched a 'Quilting Platter' recently - a set of 15 minute mini classes with a whole variety of textile artists.
It is designed by Lisa Shepard Stewart of Cultured Expressions.
You start off by folding your 10" square into an envelope shape and using it as a template to cut your wadding.
Then the 'flap' is folded up and two lines of stitching, about 1/4" off the centre point, are sewn to make a spine (or a space for a pen - I've ordered some short pens for this purpose!).