Did this for the first time recently.
Cutting straight across the steerer without a pipe cutter is hard – be prepared to file off a fair bit afterwards if not using a proper guide and/or a decent hacksaw.
For this:
Hardest bit is getting a SFN in straight. It really is worth trying to get the proper tool, either borrow or a 2 minute job in a bike shop.
I agree. Using a short bolt and a rubber mallet was really frustrating as the starnut kept twisting. If you don’t have the proper tool, then the reason that many of the youtube how-to guides suggest a small screwdriver is so that the longer part of the screwdriver inside the steerer stops the nut from turning too much.
I started with the supplied nut, but had to restart about 5 times! Worked first go with a screwdriver instead.
Oh, and don’t forget the crown race – unless you’ve a tube the right size to push it down equally then you’ll have to do what I did and nervously hit it down with a screwdriver, a little bit all round and round.