Natural light is a wondrous tool for photography. I had the opportunity yesterday to shoot in a room with a wall of north facing windows. The light coming in makes it so easy to create great images.
Great photographers through the years have often had studios with north facing windows and/or skylights. They knew that the light would give them amazing opportunities to create their work.
So you have two options in your studio. Option one is to have a wall of north facing windows to give you that great light. Windows on any side are still better than no windows. Other directions just are more or less effective depending on time of day. Sometimes I like windows with direct light on them to create the effect I want.
The other option is to fake a wall of north facing windows. To do this you need a good sized white wall. You then turn several strobes straight at the wall powered up a pretty good amount as they will be bouncing to create the light. A single strobe on a smaller white wall can work if you limit yourself to a smaller area. I like using the large wall as it just makes it easy for your model to move around the entire shooting area.
The faked wall is good, but not quite the same as the real thing. Sunlight just has a quality that the strobes can be made to come close to, but just miss.