Cory Prout explains and demonstates how to effectively strengthen the glute muscles with an exercise that can be done at home (or anywhere really)!
All you need is a piece of Theraband (available at Physiohealth) tied into a loop and about 5 meters of free space. The idea is to be into a slight squat position with your hands on your hips and the theraband around your calves.
Keeping tension on the band, crab walk sideways. Do not take big steps, just slow controlled steps keeping tension on the band at all times.