Demonstrate The Way To Dress
At this age, your child will learn most of the things after observing you. So even if you are not inadvertently making him learn something, he is actually doing it in very many ways. As far as developing a dressing sense is concern, it is always necessary to dress appropriately so that your child learns from you.
But, along with this what is also important is to teach the child that what are the things that he needs to take care when he is changing. Things like, close the room, don’t allow people to come near you, never change in front of people, etc. These will instil the necessary manners and protocols in the child too along with a suave style statement.