Simply check in on Mileslife for 7 consecutive days and stand to earn between 10-200 free miles. If you happen to miss a day, the cycle will be restarted.
The bonus miles should take 3-5 working days to appear in your designated frequent flyer programme.
The validity of this promotion is not reflected in the terms and conditions, but my initial guess was that each person is only entitled to a one-time deposit of free miles upon completing a 7-day check in cycle. Thanks to Mainly Miles, we can confirm that the promotion will last indefinitely for now, and that there is no limit to the number of miles you can get by just checking in everyday. Hence, even if you receive the minimum of 10 miles per week for the entire year, you’ll still receive 520 miles for free. That being said, if you’re so lucky to receive the maximum of 200 miles every week, you can stand to get 10400 free miles! Of course, that’s quite unlikely as the awarding of miles will most probably follow some distribution across the range of 10-200 miles.
It might be worthwhile to set a daily reminder for you to check in on Mileslife!