If you feel that your car seat is not comfortable enough, sit straight in your car, and use the levers to adjust it so that you can sit as straight as possible. Then adjust the height and steering wheel. And if your car has lumbar support, use it. But if it doesn’t come with such support, add it. Also, add something for the neck, like a pillow. Then there is always the option to use the most comfortable car seat cushion as an added measure to make the car seat more comfortable.