1. Teach shapes with building blocks or puzzles. Let the baby learn different shapes by splicing different shapes of building blocks or puzzles together. You can show your baby all kinds of shapes and let him try to find them himself.

2. Cut out different shapes with colored paper and scissors. Let the baby see these shapes and say their names. You can stick different shapes of paper together and let the baby find out the difference between them.

3. Teach shapes with picture books. Choose a picture book story of various shapes and read it with your baby. Ask the baby to point out the shapes in the story and help them understand the meaning of these shapes.

4. Make shape cards. Print out pictures of various shapes and cut them into cards. Show your baby a card every day and ask them to point out the names of the shapes on the card. Gradually increase the difficulty, for example, let the baby point out two identical shapes on the card and distinguish them.

5. Teach shapes with games. For example, to let the baby play a game of "finding differences", it is necessary to find two places with the same shape but different positions. This can help the baby better understand the concept of shape.