One goal you need to be constantly working towards is figuring out how to use the light you have to bring out your subjects. Two key areas are filling in shadows on the subject and bringing the subject out from the background. Both are very vague as they will depend on what you are trying to do but
An easy way to get the hang of bringing your subject out from the background is get a black sheet, have your subject wear black, and have at it with your lights. After a little frustration you will get the hang of it and have the basics ready for you next photo session. The reason I recommend black is that black absorbs light, making this whole exercise a bit more challenging.
As for dealing with shadows, we are in the key and fill light territory. In that area you just need practice. However, you might want to jump into low-key lighting which deals with heavy shadows to really get an understanding what is going on with your shadows on a larger scale. Alternatively, you could try Rembrandt lighting, which is just another form of low-key lighting.
Anyway, this was a two-light setup. There was an overhead light that was creating a backlight cone which helped to separate the subject from the background and a light just up front with an octagon softbox and a grid. If I didn’t use a grid, then the light would washout the backlight and defeat the point of it.