Usually if we stitch the 4 hole buttons we use x-stitch or ii-stitch, but you can make it different. Let's name the holes: the upper left - 1, the upper right - 2, the lower left 3, the lower right - 4.

* Stitch the square: the thread goes from 1 to 2, from 2 to 4, from 4 to 3, from 3 to 1.
You can combine it with an X-stitch as well, to get a more complicated look.
* Stitch an arrow: the thread goes from 1 to 4, from 2 to 4 and from 3 to 4; you get an arrow pointing to the lower right corner. You can use this arrow to draw attention to some detail on your layout.
* Stitch a flower: make an arrow just like above with a green thread, and then use knot-stitches of bright thread or use colorful beads in the hole 1 (you may want to add beads to the holes 2 and 3 as well), they will look like buds on green stems.
* Stitch with beads (good for 2-hole button as well): get the threaded needle out through one of the holes, thread a bead that is a little bigger than the hole, and insert the needle in the same hole, the bead will keep the button in place. Repeat with other holes.
* Stitch outside of the button. Place the stitches outside of the button, get the needle out of any hole and insert it in the paper near the button (NOT in another hole!), thus you can make a sun with rays or a cat with whiskers with this type of stitching.
(To make a kitty face use beads for holes 1 & 2, and stitch the whiskers from the holes 3 and 4)