Okay, many may think this is a copy from the other guide, but its a totally different way. Here are the steps.
1. You need Firefox
2. Go to the top > Tools > Add-ons
3. Select "Get Add-ons" > Browse all Add-ons
4. Search "Downloadhelper" - No Space
5. Install this to FireFox.
6. Find a video, go to options in Downloadhelper, and you're done