We believe that the best way to teach your children to be assertive is to act assertively yourself.
Since you cannot be with your children all the time, you can teach your children to be assertive by giving them specification instructions, and by “role-playing” – rehearsing common life-situations – with them.
You can use role-playing with your child successfully to teach assertion. Young children particularly like this approach because it’s like a game.
By watching you your son can see clearly how he could handle a situation. Keep switching roles, and have your child practice a few times more before trying it with a friend.