What should white-collar workers do to slim their hips?

How can white-collar workers in the office sit to slim their buttocks? :

When you sit down, you should keep your waist straight. It is best to put a lumbar support pad behind your back, and lift your center of gravity upward, so as not to put all the weight on your hips and abdomen, and make your hips increasingly hypertrophic. Girls who love beauty should pay attention!

In addition, I recommend a sitting method for thin arms to female friends: sitting V-shaped knee lift. How to do it?

1. Choose a longer stool, or a one-piece sofa, sit upright on the edge, tuck your abdomen, bend your elbows, and slowly lean back so that your feet are off the ground and parallel to the surface of the stool.
2. Fold the upper body and the lower body to one place, bend the knees toward the front chest, and straighten both arms so that the upper body is in contact with the knees forward, hold for a while, and then stretch to the starting position. Note: the abdomen should always be tightly tucked, and the spine should be straight to protect the waist. Training times: Do 3 sets of 10 to 30 reps.