Simply attempt to remain as close as possible to the usual racing position, as if you were in an authentic race car. Sitting room chesterfields, different counters, seats and bureaus will not do the work like a genuine car racing chair simulator will.
The realistic racing setting is nothing close to the abovementioned home ottomans, chaise-lounges, bureaus and stands, isn't it? So, at least you should attempt to have the appropriate racing posture. If you do not, you will not be able to appreciate the actual power and enjoyment the modern-day driving home video games are giving. It's as simple as that.