Before you start hanging lights or drawing up ideas for the director, you need to familiarize yourself with the script. You can make notes of your ideas directly in the script, and you should also highlight any specific directions given by the playwright. Break every scene down by the type of lighting you will need – outdoor, nighttime, morning or incredibly dark. This gives you a head start on the design process and lets you know how much work you should expect ahead.
A light plot is what determines where your equipment hangs in the theater. You will first need to get a list of all of your available equipment. Once you have that, a scale drawing of the stage with all available hanging rows will need to be either downloaded from the theater or drafted by you. You cannot begin to draft light setups until you know exactly what you have and where you can hang it. Make notes of the depth and width of the stage as well as the distance between the house electrics to the stage. You will also want to know the distance from the proscenium (the area between the edge of the stage and the curtain) to each of your light rows.
The easiest way to start plotting lights, once you have a light plot, is by splitting your stage into areas. Most stages can be split into six individual areas with three up front and three in the back. The action that takes place during the show will occur in one or several of those six areas, and you can work with the director to ensure the actors’ blocking keeps them in the right place at the right time. You will want a minimum of two lights per acting area to maximize the flexibility of your design, but more lights can give you more options when it comes time to start programming.
Your lights serve two roles. The first and most important job of stage lights is making the action on stage visible. The second is contributing to the mood of the scene. Every lighting scene you design should rely on visibility first and mood second. If your audience cannot clearly make out the events that are occurring on stage, it does not really matter whether the lights are effectively contributing to the mood. Walk through each scene with actors or stand-ins, and make sure the audience can always read the action on stage.