Back about 20 years ago, the area my husband and I live in was pretty undeveloped and there were very few houses on our street, so there was a lot of privacy. Not only that, the house didn't have A/C at the time, so most of the time during the day I walked around in a thin t-shirt and underwear or nothing at all.
Being the early 90s we didn't have cable or a satellite dish so I read a lot and when it was nice, I liked to read outside. Most of the time I would wear my shirt and shorts or a swim suit, but one day I didn't feel like messing with it. All I did was put on my sunglasses and stepped into my sandals and walked out almost completely bare, laid on my belly in the hot grass and cracked open my book. It felt so freeing, letting the grass tickle my nipples and vagina, I didn't get much reading done. All I could so was lay there with my knees apart, waving my feet back and forth in the air.
At that point I didn't masturbate a lot because we were having sex at least every other night, but I was getting hornier by the minute and had to take care of it. I put down my book and rolled over, spread apart my legs and started rubbing my (then) hairy pussy. I was already sopping wet, so my fingers slid in and out easily. I probably laid there for a good 15 minutes, wiggling around in the grass, moaning and rubbing my clit. When I came, it felt so nice I had to wipe tears from my eyes before I relaxed again, crossing my ankles and catching my breath. After that I grabbed the hose and watered the flowers, loving the show I was putting on before I laid back down. I tried to read my book again, but my first orgasm felt so good I had to have another, but this time I walked out further and masturbated a second time standing up, leaning against a tree. When I was walking back I really needed to pee, but instead of hurrying inside, I put my hands on my hips and squatted, letting it flow into the grass. I had never done that before, but I loved how dirty I felt afterward.
After my two orgasms I was exhausted, so I went back inside and fell back on the couch, falling asleep until my husband got home. When he walked in I told him about what I did, and it turned him on so much he took me right there, sunglasses still on top of my head and my sandals still on my feet.
I did this off and on the next couple of summers, but eventually subdivisions sprung up in the area and we lost a lot of our privacy, so my nudity had to be confined to the house. I masturbate a whole lot more now since my husband's sex drive has slowed down, and I love to do it with the windows open, but it still doesn't match doing it under the sun.