Sexting an older man

So I'm 19 and have been seeing a 31 year old for just over a year now, sexting is an important part of my relationship and I had that with my ex, but he's too shy to do anything. He can't even send me a selfie let alone a dic pic! Anyone got any good ideas on what I can do to make him more comfortable to do those things? 🤷🏻‍♀️