You must log-in and claim the Prizes for consecutive days (as in, you must NOT skip a day) in order to work your way up the meter to Day 5.
Once you reach Day 5, you will start receiving 1x DAILY CHECK IN CRATE per day. For everyday that you login past Day 5, you will continue to receive 1x DAILY CHECK IN CRATE per day. You know what they say, a crate a day keeps the doctor away!
Note that you must reload the game at least once a day; otherwise, the game won't reload the Daily Reward section and won't allow you to claim that days reward!