Good player guidance?

Seems like there's a butt-load of GM-guidance material out there. In particular things like the Lazy GM's Guide. But it's harder to find good, accessible and reasonably comprehensive guide for building good players and player arcs.

I'm a new GM, and have a few new players who having fun, but are not feeling feeling like they know how to develop their character well. Any useful material I can give them would be appreciated.

We're currently playing a game that's mechanically a bit more like PbtA (not crunchy), but advice for any game/system is welcome.