Put a large piece of fabric backing in a large embroidery frame, and grab a small piece of pretty something or other. Get some colored threads and start adding to that little first piece, folding down the edges as you sew it to the first piece, then add more of whatever shape you want.
Some folks cut these into squares and add solid strips to tie them together, others, like me, want the whole thing to look like one piece. Depends on what kind of picture is in your mind. This can be added to for years and taken up anytime you wish, put aside for any time. You can start collecting buttons, laces, ribbons, sparkly threads, premade applique or make your own. Anything goes.