I was trying to find videos on engraving a tumbler with the xTool 40-watt laser and couldn't. So I made one.

I sell customized Tumblers, cutting boards, jewelry, and other products on Etsy. Copy and paste the link into your web browser.
www.FullerBeers.etsy.com
The store also has customized screen printing.

xTool Creative Space Settings for engraving:
Power: 25%
Speed: 100%
Pass: 1
Bitmap mode: Bayer (graphics), Grayscale (text)
Lines per cm: 300 (graphics), 100 (text)
You can use fewer lines per cm if the engraving time is too long.