To be honest that part of your hips that everyone seems to be after is called the tensor fascia latea muscle. You can uisolate it by going external rotation exercises, but it gets enough stimulation from deadlifting, squatting, and some single leg type of stuff.
Don’t do any of that ballistic crap concerning your hips because eventually you will come to agitate them.
Isolation is okay, but supplement it. Don’t use that as your main focus to grow your glutes and legs.
Focus on using compound movements. One that recruit a shit ton of muscles. Stay in the 60-70% range, and feed a ton of volume into your training. Couple it with some heavy sets as well.