Advanced Glute Stretch
This is a very effective glute stretch, but the position might be hard to achieve for people with lower levels of flexibility. However, there are two different ways this stretch can be done and it can be modified more, so most people can perform some version of this stretch.
Perhaps the most common version of this stretch is called the pretzel stretch, which starts lying on the floor with one leg bent (side that is not being stretched) and the ankle of the stretching leg is placed over the thigh of the bent leg, just above the knee. While this is technically the starting position, it may be enough to get a decent stretch in the hip or glute.
To enhance the stretch, the non-stretching leg is raised off the ground, with the stretching leg still bent across the knee and relaxed as much as possible. The higher the leg is raised and the closer the stretching leg gets to the body, the more intense the stretch becomes.
Lifting the legs should be done mostly with the help of your arms, so the legs can stay somewhat relaxed. You can place both hands around the hamstring of the non-stretching leg, or one hand around the hamstring and the other around the shin of the stretching leg.
For example, if you are stretching your left glute, your right leg will start bent on the ground with your left leg bent and your ankle across the thigh of the right leg. Then place one or both hands around the right hamstring and lift that leg off the ground, so your knee comes closer to your body.
This might be a little complicated at first, but it produces a great glute stretch and stretches other muscles around the hips as well. You can make other modifications, such as your hand positions, to find the easiest way for you to raise your leg.