Sandy_paws: Your embarking on a new and exciting path, one that may or may NOT include having sex with anyone outside your primary relationship. And that's perfectly ok.
You say you don't really even think about sex. I think you should start there. You don't need to go from zero to 100. Baby steps are good.
I think Chicup is on the right track. Here's my advice for what it's worth.
Start slow, engaging in and pushing the envelope with your husband. There are LOTS of fun sexy games you can play together.
Here are some suggestions. These are intended to just get your two thinking about and communicating about sex. And feel free to open up to him. If he's worthy of your love he's also respectful of your boundaries and supportive of your fantasies.
1. Get some porn, watch it and have fun with it. Laugh at the stupid parts, act out the sexy parts and talk about all of it.
2. Visit a local sex shop and buy a few things. Not a shop too close to home. make an evening of it. Drive far enough to get butterflies in your stomach, pick up things that make you gasp. Have dinner or a drink afterwards and talk about your new toys.
One book I have seen includes coupons that you tear out can give your partner. then the partner gets or gives whatever it says. This will help you ask for and initiate sex.
3. Go out, anywhere you can people watch. Play a game with your husband. You are each going to find 5 people that you're attracted to and tell the other one about it, why? What is it that you find sexy. Their eyes, mouth, ass, hair, attitude, anything. Remember this is a game between the two of you, play with it. I have been out with my wife and we actually pick out potential partners for each other and then I, for example, describe what I think is sexy about the man I chose for her and vis-a-versa. It makes us feel connected, its us against all the other people in the world. We even talk about what the waiter would think if he knew we were having lunch and talking about his crotch and ass.
4. Get used to and try out a little exhibitionism. Strip for your husband, demand he strip for you and comment on his physical characteristics, what you like, what you lust after. Always be positive. Masturbate together. Serve him drinks one afternoon in nothing but a sheer dress or one of his shirts. Make sure he gets flashed, just a bit.
5. Flirt you asses off at a public event. Give the waitress a little extra love, wink at the bartender, comment on a strangers clothing, tell someone they have beautiful eyes.
These are just a few simple ideas, and maybe others can add some more. The result might be that you light a fire inside you, kinda get your internal flames going.
My thinking is that you start right there at home, practicing opening up a bit, pushing your boundaries and then, only after you've practiced with your man go out and start to incorporate others.
Again baby steps.
You may also find that none of this is for you.
Personally, I find people that are open and explore their sexuality, flirt, and communicate are really sexy to be around. Sex is supposed to be fun and exciting. As a guy that's been married for 30 some years, it's easy to get stale in a relationship. It takes work to keep it fresh and even more to keep it hot. Practice now and it will serve you well into the future.
Wishing you the very best in your adventures.