Just done a cambelt change and my old man come up with the best way
For starters remove the fans (2 bolts at the top are a pain) and tie the water and power steering pipes to the rack
Next remove the auxiliary and A/C belts (assuming you have A/C)
If you have A/C remove the belt tensioner
Then wrap the auxiliary belt right round the crank pulley and double it back on itself (so it constricts itself). You need to go round about twice until your left with a small loop. Now place a wrecking bar or long tyre lever through the loop and against the pulley, pull round until the belt tightens on the pulley.
Now you can hold against yourself and undo the 24mm bolt with a breaker bar.(assuming you wraped the belt the right way round to hold against youself for undoing)