After a bit of experimenting, I found that I could control this huntsman spider quite readily with a match. BTW, this is a very large match, several times longer than a standard one. I even used my finger to lift the spider (from behind ;o)) a couple of times, but I wasn't brave enough to take a shot like that because I couldn't see what was going on as clearly in case the spider decided to turn around and bite me.
The match also came in very handy for positioning the spider's legs. I found that if I brushed them lightly in the direction I wanted them to go, the spider was quite obliging, so I could set up a more or less symmetrical shot. :o) It didn't work so well if I pushed the legs, but brushing the hairs/skin worked.
The other thing I found was that the smooth surface of the mirror was handy for stopping the spider from running away. When it started to move to the edge of the mirror, I changed the slope so that the spider slid back to where I wanted it. I could also rotate the mirror to get the spider facing me (and my camera :o)). When the spider managed to make a dash off the mirror, the match was handy for rounding it back up onto the mirror, although I resorted to covering it with a plastic container and capturing it again more than once. That's how I trapped the spider in the first place, by covering it with a container and sliding a piece of card to seal off the opening.