Beginners Exercise - Step Ups!
This is a great exercise because you can do it pretty much anywhere. You can use an actual step or small stool, a ladder, pretty much anything that requires you to step up on it. Basically you are going to step up with one leg, tap your toe of the other foot on the step and step back down. Each set is 10 on each leg for a total of 20. To add a challenge instead of tapping your toe raise your knee up toward your chest before stepping back down. Work toward at least 3 sets along with your other exercises.
Here is what they look like:
Here is a good video demonstrating them as well: