The first thing to identify is the vanishing point. Your vanishing point is at eye level of the viewer. If you're creating a drawing from your own creative brain, this is important to know -- because where ever you set your vanishing point, you "put" your viewer there.
Take a look at the photos above. The vanishing point is higher and lower because the camera was raised and lowered. Notice that the bottom photo is the perspective of a REALLY tall person but the top photo is taken from the perspective of a small child. The vanishing point shifts up or down the depending on the viewer.
Once you have your vanishing point established, the rest of the lines radiate out from the center. Table tops, table legs, shelves, mirrors, picture frames, baseboards...anything that follows the walls of the room.
Assuming all of your furniture follows the walls, your drawing should be composed of only three types of lines: Vertical, Horizontal, and lines that radiate from the vanishing point.
Orange Easel is an Art School in Liberty MO. Our blog here is written by the instructors at the school.