How do I add a prop?

To add a prop, tap the pencil in the top right corner of the screen. 

Note the symbols at the bottom of the page.  A prop is a sort of X connected at the top.  

You can tap this symbol and a prop will appear somewhere random on your set, or you can draw it in the location you prefer. 

If you're having trouble, make sure you draw from the left to the right, following the red arrows.  

Tap 'Done' in the top right corner when you're satisfied. 

A prop, initially, is a white cube.  Tap it for the option bar.

Selecting 'Edit' will take you to a page wherein you can adjust the size, and color; you can customize any prop and add them to your library.

Selecting 'Shape' will take you to a page wherein you can peruse all of the different categories and prop possibilities.