So yeah … turns out I'm utterly useless with the Tamiya weathering set. (I bought the "A" version with 'sand', 'light sand' and 'mud')
My granddaughter actually asked if I was doing my makeup when she saw it. That should’ve been my first red flag. (and maybe the word 'mud'

)
Tried your method step by step - no dice. The stuff just slides off the lume like it’s Teflon and ends up smearing across the dial like a toddler with finger paint.
First attempt: dry application out of the box. Total fail. Then came water, solvent, alcohol, benzine … basically everything short of holy water. Still nothing. The paint either turns to dust or decides to relocate itself everywhere except where it’s supposed to go.
In a fit of desperation, I gave up and grabbed regular old watercolor paint. It looks like crap under magnification, but at least it stays put (more or less). Like most things in life, it’s clearly one of those “practice makes perfect” situations … and I’m currently somewhere around level one of fifty.
Good thing these cheap raffles dials exist - no need to massacre a pricey Vietnam dial while I’m still finger-painting my way through this.
Maybe I should get the other makeup set after all - but I'm afraid it's pretty much the same in terms of consistency. The Lume plots on the dials are so plastic-like - the color doesn't stick to them very well. Or maybe I'm just using the wrong technique.