|Printable Dodecahedron - Click to Enlarge|
Note that I did not draw the usual flaps that these paper models usually have for joining adjacent faces. You'll have to do that much all by yourself (it's simply a matter of leaving some extra paper on some of the edges). I would highly recommend printing to something more sturdy than your usual paper, such as card stock, so that it hold up through all of the folding and taping or gluing. You might also consider laminating the whole thing to increase its durability, but in that case normal paper would probably be better.