at 9:11 you start drawing a mask on top of the shark to make the fin. When I draw the mask my mask stroke isn't even visible
What version of Blender are you using?
These are the hotkeys I've got you can try.
Shift + LMB + Click to Select to mask
ctrl + I to invert Mask
alt + M Clear Mask
Hi patdoc, the Mask is an Overlay that (unfortunately!) has a Toggle shortcut: CTRL+M..
You are not the first to accidentally have turn of the mask visibility;)
I tried looking in the overlay dropdown and i've tried all of those shortcuts but I still cant seem to clearly be able to draw a mask on my object. do you have any other ideas?