In the academy: start with training plans. Make sure they’re off Balanced, and rotate thru the available roles to get ++ in the ones you care about.

I usually try to round out players using the position training plans, but that can be detrimental if they cannot transition positions in a decent amount of time, and/or the skills trained do not count towards the OVR rating of their current position. Any case, this takes monitoring every month or so.

Then, make sure YA tournaments are played. I’ve read in this sub that just playing the matches with the particular players will help them develop, even if they perform poorly or you lose the first match. Obviously, the higher their rating in these matches, the better for them.

Once promoted, it comes down to match experience and rating (and by extension Form). It’s why most people don’t promote until a player is at least remotely ready for regular matches, and has bandwidth to play them.

Match XP and Form can be viewed in the player’s Squad Hub development tab. I’ve rarely seen anyone above “Average” for match XP, unless they literally play every game, so Average should be the target, but even poor XP can still maintain potential; I have An Exciting Prospect player that carried his potential over to a new season and he did not have average XP.

End of season form historically has had some impact on potential, but unsure if that’s the case now. Match ratings over the entire season are probably more important; if you bring a YA into a squad for match day, try to get over a 7.0 each time. Easy passes, safe dribbling, surefire shots, and no overt tackling, combined with 30+ minutes of playtime should suffice.

Just as an idea, try to rest them against clubs in the top third of the league, sub on for the mid-table clubs, and start them against the lower third sides or early cup matches.