Thanks guys

The good thing about the gif is it shows how much extra work I did that I wouldn't have needed to do if I had the patience of - say - Lorna
Diane, apparently rubbing alcohol works well but I haven't got any yet. This is a combination of fg brush and steel wool. I use the brush near the edges and the wool for the rest, and then carefully go over the areas near the edges where I used the brush with the wool to smooth those areas off as much as I can. I assume this wouldn't be necessary if I got some alcohol (well, other than the stuff I consume while doing it

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Sue, I find the paint brush good for small areas but I did a large zebra piece once using a wash over it all with the paint brush and it ended up streaker than I would have liked. You don't get that with the airbrush.