Supplies You'll Need
The artist, Laura Poulette does give a list of supplies she recommends, however, if you already have some basic watercolor supplies you shouldn't have trouble getting through the course.
One additional item that would be good to have on hand would be tracing paper. Here is a list of items you may want to have on hand:
Watercolor paint
Watercolor paper
Watercolor brushes (preferably round size 2 & 4)
Tracing paper
Graphite pencils (preferably size #2 & H)
White eraser005
Micron pen01
Micron pen
Piece of foam core or cardboard for pinning plus pins
You can be successful with a variety of different resources, but hopefully this list will at least give you an idea of where to start. Laura also provided her list of recommended items to consider: Click here for the materials storefront.
*The link is an affiliate link.*
Also, if any of you think of other materials or alternatives that may be good to add to the list, feel free to drop some recommendations in the comments.