A collection of postcards is a great way to train your memory. Set aside a certain amount of money for postcards that you and your child will buy on your next trip. Put the date on the back of the card and describe your baby’s impressions on that day. Then punch a hole in the top left corner of the cards and tape them all together. Collecting cards with family memories will become a cherished hobby for your child. This will allow him to remember the happy moments of his childhood.