Hero Points
In a typical game, you'll hand out about 1 Hero Point during each hour of play after the first (for example, 3 extra points in a 4-hour session). If you want a more over-the-top game, or if your group is up against incredible odds and showing immense bravery, you might give them out at a faster rate, like 1 every 30 minutes (6 over a 4-hour session). You might also give them out at a faster rate during a shorter session. Try to ensure each PC has opportunities to earn Hero Points, and avoid granting all of the Hero Points to a single character.
Brave last stands, protecting innocents, and using a smart strategy or spell to save the day could all earn a character a Hero Point. Look for those moments when everybody at the table celebrates or sits back in awe of a character's accomplishments; that's your cue to issue that character a Hero Point.
You can also give out a Hero Point for a less impactful, but still notable moments. A PC landing the killing blow on a difficult foe or successfully navigating a social challenge could earn a Hero Point. There are times when the PCs' actions aren't exceptionally dramatic or world-shattering, but that shouldn't prevent you from handing out a Hero Point as a reward.
The party could also gain Hero Points for their accomplishments throughout the game. For a moderate or major accomplishment, consider giving out a Hero Point as well. This point typically goes to a PC who was instrumental in attaining that accomplishment.