Hey Sugarcrumb I had a hard time the first time using them but then I watched the videos again and they helped a ton. I found that if I run the fondant through a pastas machine on the middle setting it rolled it thin enough to push into the mold properly. I then brushed the fondant with corn syrup water mixture he mentions. I used a very pointy tool to then get the excess pieces out.
Hope this helps and good luck.