Best ways to encourage proper pronounciation?

My son is quite advanced as far as speech goes but we seem to have an issue with “B” sounds. He can make them and frequently does when asking for his sippy cup (BaBa) but is having difficulty with the word “Ball”. He says “doll” instead. Same think with the word “bike” 🤦🏻‍♀️. His pediatrician said he’s not worried and I’m not either, but I know there has to be something I can do to help it connect.

I over pronounce my B’s, point to my lips while I say the word, and repeat the word while we are playing.

I know he will eventually get it I’m just wondering if there are any ways to help him out without being too pushy. I don’t correct him because I don’t want to inhibit his self confidence. It seems like he genuinely thinks he’s saying the same word as me.

He is one.