Now comes the fun part, using the drawing tools to draw around your sketch.
First lock your sketch. This keeps it from moving while you are drawing around it.
Scale your drawing. This is very important, if you do not scale, the drawing will not appear correctly in your tour after you have updated the tour. Once you have deleted your background image, you WILL NOT be able to scale.
Choose a wall to scale, preferably an exterior wall, but if you do not have an exterior wall dimension use an interior wall.