I made a tutorial with lots of pictures on how to use Masking Fluid for watercolour a while back, and I just posted it to my website's blog for easy reference.
Take a look: http://liquidflare.net/tutorial/2018/watercolour-basics-masking-fluid/
I'm hoping to do more beginner watercolour tutorials in the future! Let me know if there's a topic you'd be interested in me tackling. :)
@Rheall I might have to pick up some masking fluid to play with. Thanks for the tutorial. :)
As for beginner tutorials, not like this is related to a mistake I made recently or anything but,
how do you go about choosing colors for shading? Gray seems kind of boring, but clearly there's such a thing as too interesting.
@nebulos oooo, that is a very good question! I'll have to make some notes and see what I can do. :D