To locate the user manual for Wacom devices by visiting Wacom's Product Resouses page found here: https://www.wacom.com/support/product-support/drivers.
Once on the page you are able to search for your product by name or model number in the search bar. You could also use the product catigory selection to locate your product.
After selecting your product, locate the "Manual & Warranty" section. There you will find a link to your product's manual.