Perhaps my experience can help with where to start. I went from being dominant in my play, to enjoying "switching" and giving up control. My current play partner is my Mistress and allows me to completely give up control. In my blog posts I have been describing how we set the scene and how I go from someone that is naturally dominant in my real life and at work to being a "good Pet". I think there are some basic things that you can do to "switch" and see if your husband will be into being submissive. For me it works because it challenges me in not only a sexually, but also in a psychological way. I love coming to "Mistresses's Place", and following her rules. Perhaps you can start slowly that way, to see if it works for both of you.
Here is a short list of how I go into a scene with Mistress;
As I enter her home, I avert my eyes away from Mistress
I neatly fold my clothes when I get inside her home
I get into position (naked of course) on my knees with my hands on my thighs, with my palms facing up
I wait for her to put on my collar, or anything else she chooses
Occasionally she will ask/tell me to assist her in dressing in her outfit
I do not speak unless told to
I am inspected for neatness and cleanliness
I must crawl to her or where commanded
I must get into the position she commands and await......
I must communicate, by "thanking Mistress " for whatever she does to me
If I am spanked I must not turn away or move and must receive each spank or lashing without moving
I think you get the idea. I write this to suggest you start with the little things and see if you or he find enjoyment in switching roles.
And never forget, communication is the key in setting expectations before, during and after. No always means no.