The key to accuracy in SketchUp is the little text box that lives in the lower-right corner of your SketchUp window. This box is the Measurements box, and here are some things you can do with it: Make a line a certain length. Draw a rectangle a certain size. Push/pull a face a certain distance.Change the number of sides in a polygon. Move something a given distance.his box is the Measurements box, and here are some things you can do with it: Make a line a certain length. Draw a rectangle a certain size. Push/pull a face a certain distance. Change the number of sides in a polygon. Move something a given distance.