The printer arrived, I levelled the bed badly, and printed a benchy that looked like it had been left out in the rain. This is, I'm told, the correct way to begin. Nobody's first prints are good, and the failures teach you faster than the successes, so here's a week of failing in roughly the order I failed.
The first lesson was adhesion, which is to say the first lesson was about the first layer and nothing else. A print that won't stick to the bed has already lost, and everything you do afterwards is wasted plastic. My early attempts curled up at the corners and detached halfway through, leaving a sad tangle the printer kept extruding into. The fix was unglamorous: get the nozzle genuinely close to the bed, level it properly rather than approximately, and slow the first layer right down so it has time to bond.
The second lesson was temperature, and specifically that the number on the spool is a starting suggestion, not an answer. Too cold and the layers don't fuse, so the part delaminates if you so much as look at it. Too hot and you get stringing, those fine whiskers of plastic strung between features where the nozzle oozed while travelling. I printed a little temperature tower, which is exactly what it sounds like, a tower printed in bands at descending temperatures, and read off the band that looked best. For my PLA that turned out to be a good ten degrees below where I'd started.
The third lesson was patience, which I'm worse at than the other two. A print that's going wrong will keep going wrong, and watching it hopefully does not help. Better to cancel early, change one thing, and try again than to let a four-hour print fail slowly while you tell yourself it might recover. It won't. Change a variable, re-run, take notes.
That's really the whole game so far: change one thing at a time and write down what happened. Bed adhesion, temperature, then speed, in that order of importance. Get the first layer to stick and you've solved half your problems before the print is a centimetre tall. I've got a small graveyard of curled, stringy, delaminated little boats on the shelf now, and somewhere in the middle of the pile is the first one that actually came out clean. That one I'm keeping.