You can feed every 5 days, I feed every 7 days or so, depending on the age of the snake.
The rule of thumb is feed prey that is 1.5 times the size of the widest part of the snake. You can also weigh the snake, & follow the Munson Plan
-When they're on single pinks (2-3g), I feed every 4-5 days. (Snake = 4-15g)
-Double pinks (3g x 2) every 4-5 days. (Snake = 16-23g)
-Small fuzzies (5-7g) every 5-6 days. (Snake = 24-30g)
-Regular fuzzies (7-9g) every 5-6 days (Snake = 30-50g)
-Hoppers (9-12g) every 5-6 days (Snake = 51-90g)
-Weaned (14-20g) every 7 days (Snake = 91-170g)
-Adult (24-30g) every 7-x days (Snake = 170+)
-Jumbo Adults (40-50g) every 7-x days (Snake = 400g+)
Note: Adult females are fed more frequently than adult males (especially following brumation). Females are fed every 6-8 days; males are fed every 7-14 days.
I wait until the animal is a few grams past the "move up" weight, before I move them up to the next size prey