I'm a film dork and I was watching There's No Business Like Show Business (which is a musical) and there was a number with a girl who was pretending to be French and she had these GORGEOUS shoes, pitch black with pink rhinestones on the heel. Then I saw Evelien's Disco Shoes: http://www.cutoutandkeep.net/projects/disco-shoes and was like... what if I COMBINED them?!
I bought two sizes of crystals. Small ones and bigger ones. For the most part I used the bigger ones.
The crystals I got are called Crystazzi (at Michaels) and the upside stick to a sheet with the flat part on the back. I applied a little dot of glue, and used the clear sheet to place the crystal, hold it down and then peel it off. Most importantly, this gives you a barrier between you and the glue and you don't have rhinestones stuck to your fingers for 2 days...
Now, sometimes the glue causes this "frosted" appearance on areas it touches.
<- See it over there? Ew!
Nail glue is a lot better than super glue, but still not perfect. One thing I'd suggest (but didn't do) would be to put masking tape over the leather part of the shoes to avoid this. Or if you're like me and it gets all frosted, whip out some acrylic paint and paint the whole shoe.
It's not that noticeable when wearing, but if your a perfectionist, it might bug you.