Ride bareback a couple of times and relax. Try to move your hips as the horse canter.
try and think of your hips absorbing all the movement
Sit up straight and maintain a good balance with your horse. Move your hips along with the movement your horse is making.
Imagine you're a dressage rider and sit up tall and think of leaning back! Look up and enjoy your ride 😊
Imagine you're drawing a big circle with your pelvis. Also if you are able, have a lunge lesson and go stirrupless, it really helps when you can't rely on your feet to help you!
Try to sit and your butt bones and let yourself sink into the saddle
Relax your core muscles and your lower back and and imagine you are polishing the seat of your saddle with your bum
sit deeply in the saddle, relax, and lean a touch backwards