When you use something...

"When you use something on your character sheet, mark it for experience. When you mark the 7th, improve and erase your marks."

This seems kind of vague (when exactly am I using something?) and also a bit fussy, like I'll be marking 3 or 4 things all at once.

For Oaths in particularly, is "using" it when you follow it, or when someone else determines you've followed it at the session's end?

Examples of vagueness from the Dragon Herald playbook, with possible "use":

• Dragon's Blood: when you would have been harmed by fire?
• Inviolate / Armor: when your armor reduces harm?
• Otherworldly: whenever you roll Weird?

Thanks, Bret!

Most of the things you mark, you roll for, or use mechanically in some way, so it'll be clear when you've used them. Sometimes, yes, you'll mark a few things at once.

For oaths, you mark them at the end of the session.

Blinks: exactly right.

-Vincent

Under what circumstances would you check a notable follower?

This is an extremely fair question.

-Vincent

Related question:

What about moves that replace moves?

For example the Troll Killer's Fearless move: when you draw a monster out, roll Cool instead of rolling Hot. Would you only mark XP for Fearless? Or would you mark XP for Fearless AND Draw someone out?

Mark both.

I may decide to take the XP checkboxes away from notable followers, stat substitution moves, and some other things, but I'll need to play a bunch myself and watch what happens before I decide. For this document, everything got one.

-Vincent

I may decide to take the XP checkboxes away from notable followers, stat substitution moves, and some other things, but I'll need to play a bunch myself and watch what happens before I decide. For this document, everything got one.

FWIW I like the checkboxes on the followers, it encourages the players to (re-)incorporate them into the fiction.
rgds
rob