For this experiment, you only need a black pen, 10 pieces of white poster board cut into 11” by 11” squares, and a box of 1” red dot labels.
Now make the first 10 quantity cards your baby will see. Card 1 has only 1 red dot, card 2 has 2 red dots, etc. The last card in the set, of course, has 10 dots. Make sure the dots are arranged randomly on the card, in no patten whatsoever. Label the back of each card with the appropriate numeral.
Choose the perfect moment and show the baby the 1 card, the 2 card, and the 3 card, simply saying “1,” “2,” “3.” Come back a little later and show the cards again, but change the order. Show them later a third time in a different order. Repeat this tomorrow and the next day.
Then, put them away and start cards 4, 5, 6 (3 times a day for 3 days). In this way work your way up to 10. Your baby has begun to learn the language of mathematics and the perception of quantity.