Helpful, but not necessary, is a jig for forming the star. I used the side of an old drawer to drive some nails into to wrap the wire around, 3/8" plywood or thicker would likely do the trick if you've got a bit laying around. As long as it's thick enough that the nails are driven in about halfway; you do not want the nails pulling out as you are wrapping your wire around them. The piece of wood that I used measured 15" by 10" or so, and was heavy enough that I was able to manipulate the wire around the nails without the whole thing flopping around. If you are worried about such things, a C clamp or a Quick-grik clamp or something similar would help keep the jig anchored while you wrapped the wire with both hands, if you found it necessary.
materialsfor the jig (optional)*
piece of plywood or a board at least 3/8" thick, at least 10" square-ish.
qty  1 1/2" finishing nail or smililar.
for the stars
16 gague galvanized steel wire, or another firm, non-rusting hobby wire. (I used OOK brand)
beading wire, ~ 20 gague, finer (a smaller number, like 18, or 16) to accomodate some seed beads.
assortment of beads and buttons in a variety of colors and sizes
wire cutters (a combo of the pliers/cutter is helpful, but not necessary)
instructions - this star ended up being about 4", not counting the loop at the top [pictured above and below]
Start by creating a star form using either the jig*[using a jig? really, see this section] or make one free form. Have about 6" total of wire reserved for the end of the star, 4" of wire for the hook, and about 2" on the opposite end for the wrap. A curly-cue is a nice place to start for the hook of the star; if you really want to get fancy, you can branch out to things like G clefs later, after you've perfected your wire wrap technique. Bend the points of the star, until the other end of the wire is back at the beginning, and wrap the end around the middle of the stem below the hook. It's okay if the star's top isn't quite as pointy as the rest of it. Wrap the end once or twice around, and then trim the excess wire off with the wire cutters as close to the stem as you can.
now for the fun part! [if you are doing this project with a bunch of small children or impatient people, have the stars made ahead of time.
one you have your star form secure, take your beading wire and cut a a generous 24"; this gives you enough to wrap a small amount securely as a starting point, have enough to string your beads on, and enough to wrap off at the end. Take one end of the wire, wrap it around the top part of the star a few times to secure it in place, and start stringing beads. Or buttons. Wrap the wire around an arm of the star, and start stringing more beads, weave around other strands of beads, and keep going until you have about two inches of wire left near an arm of the star. Wrap the end off, tightly [you don't have to use all of it] and trim off any excess as closely to the edge of the star as you can. Viola! Done!
the jigwhy 10 nails and not 5? you need a nail for each of the points that the wire has to bend at, so not only the acute points the of the star, the pointy- points, but the obtuse angles, the interior parts where the star comes in at.
Remember, when using the jig to form the star, the wire goes on the INSIDE of the nails that aren't the points and around the OUTSIDE of the points.
If you're not comfortable free hand drawing a star, find a picture of a star you like on line, print it out, and use it as a guide for where to drive your nails for the jig. The good news is that it's paper, so when you're done hammering, you can rip the paper off, no harm, no foul. As you can see, I use the side of an old drawer as the base for my star jig; if I wanted to, I could make a second, smaller star jig on this board, and get a two-fer out of the deal.