As you will see, there is a lot of overlap between strength and balance exercises; very often, one exercise serves both purposes.
Any of the lower-body exercises for strength shown in the strength section also are balance exercises. They include plantar flexion, hip flexion, hip extension, knee flexion, and side leg raise. Just do your regularly scheduled strength exercises, and they will improve your balance at the same time. They can improve your balance even more if you add the following modifications: Note that these exercises instruct you to hold onto a table or chair for balance. Hold onto the table with only one hand. As you progress, try holding on with only one fingertip. Next, try these exercises without holding on at all. If you are very steady on your feet, move on to doing the exercises using no hands, with your eyes closed. Have someone stand close by if you are unsteady.
Don't do more than your regularly scheduled strength-exercise sessions to incorporate these balance modifications; remember that doing strength exercises too often can do more harm than good. Simply do your strength exercises, and incorporate these balance techniques as you progress.
Also do the knee-extension exercise shown in the strength section. It helps you keep your balance by increasing muscle strength in your upper thighs.