Yeah... like the other guy said, the easiest way (assuming the file is smaller than 750MB) is to just click the "Upload videos" box. That will upload the video directly to the site using Turbo.cr. (You'll most likely have to log in first to Turbo). If it's larger than 750 you'll have to either find a way to compress it (using something like Handbrake) and then use Turbo, or use a one of the third party sites that are accepted on this site. I suppose you could also use something like Lossless Cut to simply chop one large file into multiple smaller ones to fit under that 750MB limit.