Scale figures can be as simple as you want. They don’t need to be detailed to be effective. Stick figures or silhouette people standing upright are fine as long as they are at scale with your drawing. Use them liberally while working.
Try placing some figures at your entrances, or on top of a platform, or in front of an important design element. Are the steps too steep for a person? Can you get into the door with ease? Is there enough room in your design, or do your scenic elements crowd it? It’s easy to draw a perspective view of an idea that looks big and dramatic on paper, but once you put some scale figures into the perspective view, you might realize that there’s not nearly enough room to do anything in it.
Draw a few paths between the figures, charting where your actors might go. Is this path too difficult, too tight, awkward in some way? Can your performer get around the set piece they’re standing next to easily? You should be checking scale figures into your plans, elevations and perspective drawings often, to make sure the spaces feel realistic once people are placed into them. It may even help to make a series of scale figure cutouts, and place them on your floor plans and sketch ideas, to see what areas work or don’t work.
Scale figures aren’t just for plans. Once you’re working on your model boxes, you’ll have little standing people at the same scale as your model so you can visualize scale in a 3-D environment. Is the wall in the foreground too high? Does the railing line up well with a person’s hip or elbow? Are there objects on top of walls or furniture that seem awfully high or low? Check all of these areas out with scale figures in your model to make sure everything is working.
It’s also important to use scale figures to check if the performer will stand out against your background. The actor is the most important object on stage, so make sure they’re not getting lost. This means you’re not drawing one giant background wall with nothing else going on. But you might also find that your focal point is the table center stage, and it’s competing with the actors on top of it. Think carefully about what the audience should be looking at, and make sure the performer is always the star.
This is where scale can really come into play. If you have a balanced design of mass and negative space and a focal point that still allows the performer to be the main element on the stage, then your design works. If your design only works without people in it, you probably need to reconsider some of your choices.