How are you having trouble with the long-tail cast on? Are you unable to do it? Or are you casting on but are unhappy with how the loops are forming on the needle?
If you're having trouble following the video, you might search for some written instructions with images to help you out. Here's one such article with images (scroll down to see long-tail cast on): http://knitty.com/ISSUEsummer05/FEATsum05TT.html
If you're casting on but are unhappy with how it looks, all I can say is practicing will help. First attempts always look horrible!