Indexing wheels (also known as an division plates or a indexing plates) get used for a number of operations on the rose engine.
For example, to make a basket weave pattern
Indexing wheels like the yellow one shown on above can be made with 3D printers, or they be purchased. I purchased an aluminium one from Alisam Engineering.
The video below shows a number of things, including the use of an Alisam index wheel (around 2:35 into the video).
Spiral Fluting an Ornament on a Rose Engine