Ideally, you will be able to test out the chair you want to buy in person. However, if that is not a possibility, consider the size and shape of your body and see if you can find reviews by anyone who fits a similar description.
There are some kneeling chairs with adjustable heights and angles of the seat to cater more to the needs of your body and your seating arrangement. These are particularly useful if you are ordering a chair that you have not had the opportunity to test in person. A good quality kneeling chair will provide years of use and will help improve your posture, and potentially, even your overall health.
While you are outfitting your workspace for your comfort and well-being, you might also consider additional modifications. For instance, lifting your screen with a monitor mount or stand can keep your neck straighter and finding the right ergonomic keyboard will help you avoid wrist and arm strain.
Additional information: These statements and any information contained herein are intended for educational purposes only and are not meant to substitute for medical care or to prescribe treatment for any specific health condition. Carefully review product labels for instructions and important safety information and consider consulting with a health care professional regarding your use of health and wellness products.