Get images that have the best contrast between the model and its background. That makes it much easier to make the model float in the final steps. If at all possible, use a background color that isn't even remotely part of the model.

Always maintain EYE LEVEL. This is very important. Think of yourself as a scale figure in the world of your model. Your line of sight should be parallel to the ground and roughly five feet from the ground. If you don't get this right the perspective won't match and your compositions will always be a little bit off.

Pay close attention to the notes you took while doing site photos. If at all possible, refer to the site photos as you are taking views of the model. Make sure that the intensity of the light and its direction match as closely as you can get it while taking the views.

Take a lot of photos. The more you have the better match you will get. And you won't have to set up the camera and start taking photos again.