Do great artists plan their art before they start working?

A good answer might be:

Yes, usually. Artists make sketches, and small preliminary drawings before starting on their big projects.

It is useful to use graphpaper to plan an image. If you are planning to use the Java graphics methods to draw a picture, it is useful to use graph paper first. Here is a picuture laid out on graph paper:

QUESTION 2:

Say that you decide to make a picture that is 350 pixels wide by 250 pixels high. (Mentally) label the grid lines of the graph paper in the above.