During the offseason they get a small per diem to come in during workouts. Players who haven't made the team and their just for camp fodder get a decent hourly wage. Most players have some kind of bonus they can qualify for if they make all their offseason workouts or even are just still on the roster by like June, for example.
Once camp begins they qualify for additional bonuses after their physicals. And after camp ends and the season begins, the paying begins.
Players are paid weekly and their signing bonuses are spread out through each paycheck by each year the total is appropriated. If a player is injured, he doesn't always get all his salary. Some players have contracts that give them less money if they don't play. Some have it worded where they need to be active or start to get certain escalators.
Once the playoffs begin there is a small bonus all the players get for playing in a playoff game. 23k for home wild card players and 21 for the road wild card teams, 23k for the divisional game, 42k for the conference and the Super Bowl nets you 92k if you win and 46k if you lose.
They make all their real money during the regular season, so they need to save it. This is also why some players get into trouble during their bye. They have money to burn and want to use it.