What to do if i have 5% scoliosis can people like sit a certain way or like do something to start increasing there scoliosis?

Depends: Usually exercise and physical therapy is the mainstay of dealing with issues from scoliosis. Sometimes depending on how much curve you have you might benefit from a brace as well. I would speak with a good musculoskeletal/spine physical medicine & rehabilitation doctor or even an orthopedic spine surgeon.

First, to be defined: a scoliosis the curve has to be 10 degrees or larger with any curve less than that not even being labeled as one. So you do not have to worry about any particular way of sitting or pjs tire or activity to cause any further changes.

Maintain good postur: Keep aware of good posture, look at yourself in the mirror and try to maintain a symmetrical appearance. Avoid hunching. These are good habits for everyone.