You just saw a photo that gave you an idea for a painting or a sketch but you don't want to copy the exact picture. You want to put two or more things together and add your own touch but you're not yet that skilled to be able to come up with stuff to put together so what do you do? Here's what I do - I first, map out my idea, the background, the subjects I want on it, where I'd place them in the sketch or painting, then I'd look at books, magazines or anywhere I could get a picture of the subjects I want in the sketch (since I'm still a newbie and isn't yet expert enough to draw them from imagination). Once I have what I need, I then sketch the background first, then the subject/subjects. For example: i wanted to do a bird on a piece of a tree stump but can't find a picture that has that exactly, so, I first looked for a picture of a stump and only copied the stump and then from another resource copied a bird and put the two together.