Teaching your child how to use a toothbrush is an important skill to help children develop good oral care habits from an early age. Here are a few step-by-step instructions to teach your child how to use a toothbrush:

Choose the right toothbrush for your baby: Choose a toothbrush that's the right size for your baby's age. A toothbrush needs a small head and soft bristles to clean teeth gently and effectively.

Teach your baby how to brush his teeth: Teach your baby how to brush his teeth by placing the toothbrush in his mouth and using gentle circular movements to clean his teeth. Your baby needs to brush both the upper and lower teeth, the inside and the outside of the teeth, and pay attention to the spaces between the teeth. If your child does not know how to brush his teeth properly, you can use your hands to guide him on how to brush his teeth.

Teach your baby how to use toothpaste: Let your baby learn to put a small amount of toothpaste on the toothbrush and use it to brush their teeth. You need to teach your child that just a small amount of toothpaste is enough to clean his teeth.

Show your baby a pattern: Model your child by brushing his teeth with him and show him how you brush, especially how you clean between teeth.

Encourage your child to brush properly: Encourage your child to brush properly by praising her when she brushes her teeth correctly and completes her daily brushing. You can use positive words of encouragement to encourage your child, for example, by telling him "he brushes his teeth well" or "his teeth are clean and healthy".

Make brushing fun: You can help your child see brushing as a fun activity by letting him choose a favorite toothbrush or a flavored toothpaste tasty. You can also let your baby listen to songs or short stories while he is brushing his teeth to keep him interested and not boring when brushing his teeth.

Daily Brushing: Encourage your child to brush his teeth daily, at least twice daily, in the morning and at night before bed. This helps remove bacteria and plaque from the teeth, keeping your baby's teeth clean and healthy.

The steps above help you teach your child how to use a toothbrush effectively. Besides, you should ensure that your child brushes his teeth daily and take him to the dentist periodically to check and take care of his teeth.