Use a piece of wooden dowling with a blob of bluetak on the end if you dont have the correct tool. Dont be tempted to fit your electric drill to the collet end of the valve and spin them up that way or you will overheat the seats and the guides.
pop down halfrauds or a motorfactor or a spares place and get a grinding stick (aprox £2 ) and some paste (double ended tube that has course and fine is about £5 off the top of me head)
are you near there? give your local factor a ring and ask them if they can deliver if you pay cash on delivery, if you are in there delivery area they should oblige