Denim jackets aren’t really my wheelhouse, but I’d take a look at suitsandboots to get some inspiration. I think he does quite well when he wears the denim jacket.
I’d probably try to treat it a bit like any other layering piece, except in a casual manner. Maybe skip the necktie and go with a plaid button-down collar, crew-collar sweater and then the jacket on top. I’d avoid wearing indigo denim and instead go for another colored jean (tan, white, olive) or go with chinos (except maybe navy).
Hope that helps.