So, a side lunge on a bosu ball you can do several different ways. The most basic one and probably good start, starter to warm up, even if you are doing a more advanced version is to just have one leg a little bit further out than your hip and then definitely the other leg further out than your hip because it's on the bosu ball in the middle. And you're just going to go down. You want to keep your hands somewhere in front of you, so maybe a prayer. You don't want to put them on your hips, really. So, you can put them out on the side. Out of the way, anyway. So, you're going to come down. And then what you really want to concentrate on is your knee not passing your toe and your butt basically in line with your knee. So, you're going all the way to point where your knee and your butt line up. You'll really feel it right there in the glut. And then you'll come up. So, very basic. Just to warm it all up.