Never done anything actually barefoot
Like others have said, start slow. More barefoot time at home indoors is a good start. Start transitioning to outdoors slowly on softer surfaces. Tender feet are not for rough trails.
I hike for miles barefoot but it took some time to build up to that ability without serious injury. Go for softer surfaces or shorter exposure starting out.
Somebody said the beach. If thats nearby the sand is a really great place to get barefoot time in!
It's best to start out slowly -- especially if it's your first time -- I grew up barefoot but got off track. I think it was easier for me to get back to it because I knew what the rewards would be.
So, stop wearing shoes, slippers, or even socks in the house.
Walk barefoot in the grass. Kick your shoes off at the park. If you go to the pool, don't take flip-flops with you.
Before you freak out about getting athletes foot at the pool or in the locker room, understand that it cannot live on bare feet. If you already have it, you'll probably need some sort of creme or ointment to get rid of it, but once it's gone, if you're barefoot all the time, it will not come back.
Now, here's the harder part, you're going to have to push yourself out of your comfort zone. You need to walk on rough surfaces -- a little and first and more as you progress. Also, hot surfaces will encourage callus growth on the bottoms of your feet. Yes, you need a thick callus layer so you can walk on essentially any surface. Heat is very effective in developing calluses, but don't burn the bottoms of your feet.
Something to keep in mind. In the US, there are no laws requiring an ordinary person to wear shoes at anytime, in anyplace, for any reason. The Health Department regulates businesses, not customers. OSHA is about employers and employees -- not customers. The only people who are required to wear shoes while driving are people engaged in commercial driving -- you know, truck drivers. If you don't have a commercial driver's license, you don't ever have to wear shoes while you drive.
Work at it slowly, but keep pushing yourself. You'll get there.
As a nudist you're probably already naked at home, and it's really easy to just start being barefoot there as well. Just take off your shoes and socks and get used to the sensations on your feet as you hang out and go about your home.
Feel the sensation of nothing but skin from head to toe? Pretty awesome isn't it? I and many, many other nudists go naked and barefoot at home without a stitch, and that's often the place we're naked most often and can be naked the longest. It's really nice! Try it! You have nothing to lose but your shoes and socks, lol. And afterwards you'll REALLY have nothing left to lose because...nothing left to remove from your body at all!
One piece of warning....... Old asphalt is the worst! Especially on a hot sunny day. I can walk for miles barefoot on concrete, but after a mile on asphalt my feet feel raw. If I plan to walk any serious distance on asphalt, especially on a sunny day, I break out my Xero shoes.