Number one homework rule: Don't try to do your homework in your "lazy" place.
We all have a lazy place, and most of us have more than one. Your lazy place is where you go when you want to get away from work and worry, and just relax. It might be a special seat in front of your television, or it might be a spot in the middle of your bed where you like to put on headphones and listen to music. We all need this space for enjoying down time.
But I think it is important to make a clear mental distinction between your lazy place and your work space, and to never cross those lines!
You can give yourself a psychological handicap by attempting to do your homework in a space that your brain relates to "off time." If you have a special chair where you go to watch TV or play games, your brain just might get used to being on autopilot in that atmosphere. This could make it hard to concentrate in that space. You can probably do your work there, but it may not be your best work!
It's much better to designate a special place for homework (even if it's a different chair or a bean bag) and make that a designated work place. This could cut down on the "wandering mind" problem.