XP The force of which shapes the game.

 No matter what role-playing system you play, there is a means to advance your character with new abilities or skills. Some systems are more abstract than others in the "rules" of gaining XP or experience points, in reality the GM (Game Master) is the ultimate arbiter or rewarding his players.

This is where the GM has a power within the game to give rewards to specific actions in the game, thus promoting specific behaviors that the players, if they choose to ignore, lose in the reward.

GM's who tire of their players being murder-hobos can use the XP rewards to cull most behaviors in this instance. After all the RPG (in all systems) should be only viewed as a toolkit, not a legal document of rules, to be followed as a guide.

In my latest Numenera Tabletop game group, the players are adjusting from a traditional 5e D&D mindset, to something totally new and alien to them. The strange land and all its mystery is astounding my players along with the traditional RPG mechanics being tossed aside (meaning, the idea behind no initiative rolls in combat, and the GM does not roll dice, giving an air of the GM working with the players, not against them, being forefront).

I myself, adjusting to the game as well as a GM. This is my second group of players, only running Numenera once before. I am also discovering the XP system within that game quite versatile.

FYI: I've found even from my first game with Cypher, this game really is my jam. I'm challenged to come up with a lot of  "linking" concepts on the fly, and learning to go with the flow of the players insights and assumptions, using them as resource to pull idea from, without their own knowledge of it happening. Also note, I have all the card sets, and they have excellent ideas that I can pull from as well.

In my Castles and Crusades sessions, I use a checkmark system for each player. I have a sheet of paper with each characters name and a tally of checkmarks beside them. Every time I reward the player for a class-centric idea or success, I reward them 2 checkmarks, for other outside-class successes, I reward one. 

The checkmarks can equal 100xp each is you want or 50xps, depending on the style of session, and I reward the summ in the end of the scene/dungeon/adventure when the party has their downtime.

As a GM, you have to remember to put in challenges for all of your players classes (if the system use classes) so each player can shine in their particular roles.

Letting your players know where their XP gains are better, helps in them understanding what character behaviors you want from them. Announcing bonuses during play will give them hints on where you are giving them better rewards.

This might not be for every GM, as everyone is different, but this seems to work for me in a campaign setting. One shot sessions being different, and I usually run one shots with players with hidden agendas to complete as goals.