Do you know the days of each month?
This simple rule of the two fists will help you figure out the numbers easily.

1. Clench your right fist.
2. Start counting the months from your right index finger’s knuckle, the first convexity, and continue with the next concavity, the space between the index and the middle fingers’ knuckles. Every curve corresponds to a month so that the first convexity is for January, followed by the next concavity for February.
3. The last convexity on your right fist is for July.
4. Now, clench your left fist.
5. Continue counting the months from your left index finger’s knuckle - August. December will appear as your left ring finger’s knuckle.

You must only remember that the convexities (your knuckles) mean 31 days and the concavities (the spaces between knuckles) signify 30 days (28 or 29 for February).