Read the script of the play you are designing the set for. It is important to have a full understanding of the play itself so you can begin to think about scenery and scene changes and how they are going to flow. While reading the script, make notes and jot down ideas as you go.
Meet with the director of the play to obtain his/her thoughts on the set design. The director will have the overall say with the production; his approval and input are crucial. Also, how the director will be directing the actors will depend on set placements. It is important to come to a mutual agreement on the set design.
Lay out each scene on graph paper. Draw how the stage will look as if you are an audience member facing the stage. Use a new sheet of graph paper for each scene; put scene-change notes in between each scene. For example, when changing from Scene 1 to Scene 2, put scene change notes after the graph paper depicting Scene 1. Use a three-ring hole puncher and place papers in a binder for easy reference.
Make a complete list of items you will need. Think about storage space and how easily pieces will move. Whenever possible, have items serve a duplicate purpose. For instance, a kitchen table can also serve as an office desk.
Draft a time-line and work schedule to make sure there is enough time to complete building the sets. Re-evaluate often and see where you may be falling behind and if you might need to put in more hours to be finished on time.