How can you get skinny legs quick?

Running a lot will strengthen the legs without adding a ton of muscle mass like weight lifting would do. And it will burn fat off the legs. There are limits as to how thin you can make your legs, and it is set by genetics and your body "type" as well as your metabolism. Get some input from someone who is a trainer before making any decisions to alter your shape. Note that a lot of regular long runs (the best medicine to make your legs thin) should only be undertaken after a medical consultation. And it will involve what the rest of your body looks like and how you eat. It's a package deal, and there are no shortcuts - no matter what anyone says or is selling. Period. It's your body, and you have to live in there. Make good (and informed) decisions about what you do with it.