Well, guess what I'm doing at the moment
Jack the bike up, or leave on main stand but raise 2" off ground
undo caliper and tie up from frame (or if drum don't do this)
Take off speedo drive and front wheel
undo the clamps for the legs and twist down and off the bike (that's why you jack it up)
tricky bit.....
use an 8mm (i think) Allen key under fork leg and clamp leg in vise. (you have left the springs in didn't you?)
using a shock/snap motion, loosen and undo the bolt. you still have oil in so be careful. leave standing on a bowl to let oil drain out (pref overnight)
If the bolt turns but doesn't undo, come back on here as now it becomes a pain.
Repeat for the other leg
get the wife to take out the circlip whilst you push down on the top spring securing plug. (my missus has done this before and is really good at it. If you're lucky you can get her in a position so her tits rub on your arm, Bonus!!)
take off the lower fork leg circlip
Prise out the seal with a tyre lever and use heat. Mine has come out easy as i did this a few years ago and greased (ACF50) the seal
watch for a spacer under the seal
clean all the crud at the bottom of the leg
drift in the new seal making sure it is the right way up
anneal the copper washer for the allen bolts and check for any signs of wear
reverse procedure for assembly (inc the missus help!)