All the important technical detail is covered in the service manual.
It does miss out some steps about some things to remove and refit though, but you'll suss those as you go through it.
Re:the auto tensioner, when you back it off, what it doesn't tell you (so you don't expect it) is that the screw is heavily sprung loaded. You need to press down on it to keep the screw driver engaged and you must keep the turning force on it at all times, otherwise bang! It will release again. TBH the auto tensioner makes tensioning the bolt a piece of body lemonade though, it's great.
Most difficult bits of the job imo:
Space to remove/refit the lower cam belt cover (honestly, this is one of those pics little things that is a complete and utter rhubarb
)
Space to squeeze the belt through between the chassis arm and the engine mount bracket on the engine (I found I needed to lift the engine to create enough space, which I did by using a long pry bar on top of the toe arm and under a part of the block casting that sticks out the back of the block, just above the sump)
Keeping the cam gears aligned while you fit the belt (found it is so so easy to go a tooth out on this engine and then it's a pita having to take everything off again)
Front balance shaft alignment is annoying because you cannot get in there to see it first hand. I used my phone to take pics and check it. Then have to be really sure to make sure you hold the pulley stationary while refitting.
Crank pulley nut (obvs) probably OK if some rhubarb hasn't locktited it
Accepting that yes, the balance belt really is meant to be that slack when tensioned...
If I wasn't checking the water pump and tensioner pulleys out, I would have done the car SOS cambelt change trick - saves masses of time and fiddling around with tensioning and timing etc.