Biggest time saver is getting yourself properly organised before you start.
Separate places, with labels, for the new O rings et al organised by what goes where and similar places for the old parts being replaced and things being removed and refitted as part of the process to go. Not forgetting places to keep the screws in order.
Obviously fairly detailed notes / labels as to whats what, where it goes and which side of the block you will be working on.
I suspect that sorting a proper notes and places system is a almost as effective a learning tool as doing your first one. Likely to take an hour tho'.
I'm fairly methodical but wasted ages first time through with an O ring and "did I / didn't I" mix up. Primarily due to thinking that simply laying out on the bench would be good enough. Not quite. Most likely due to disorientation when flicking between the how to notes printed off the internet, the block and the bits being taken off / put on. Once I'd lost my place in the sequence trying to figure out exactly where I was at was hard.
Got a check off list for doing the brakes for similar reasons.
Clive