Nine prints out of ten on my machine fail or succeed in the first layer, and the first layer is entirely about how level the bed is and how close the nozzle sits to it. Too high and the filament lays down as a loose round noodle that will not stick. Too low and it scrapes, starves, and you get nothing but a sad clear smear. The window between those two is maybe a tenth of a millimetre, and it drifts every time I so much as look at the printer funny.
The method that actually works, after much faffing with feeler gauges and fancier rituals, is still a sheet of ordinary paper. Heat the bed and nozzle to printing temperature first, because the metal moves as it warms and a cold level is a lie. Home the printer, drop the nozzle to the bed at each corner in turn, and slide the paper under it. You want a faint, consistent drag: the paper moves, but you can feel the nozzle catch it. Same drag at all four corners. Adjust the wheel under whichever corner is wrong, go round again, and again, because tightening one corner nudges the others.
That is the whole war. Heat first, paper drag, round and round until the four corners agree, then a single-layer test square to confirm. It is tedious and it is never permanently won, but ten minutes of it up front beats watching an eight-hour print peel off the bed at hour seven. Again.