I've had amazing success with the tucking panties from tcomfifits. I just can't do the tape method, and these always hold everything in place when I'm out! I'll wear them the entire day and rarely feel any discomfort. My only wish is that they had a few more styles, buuut I received an email from them recently that made it seem like they might be expanding their options!

I don't tuck and don't know beyond trusting spiro to do its job. Responding because I thought the title was "advice on fucking" which I can definitely provide. :)

I'm not exactly sure what you'd call them in English, but I generally wear something like bike shorts? Underwear, but the kind of thing you'd have on under a skirt for modesty. They extend a short way down the leg, so there's plenty of material to hold everything in place. I combine that with some undersized panties if I'm going out and really need to make sure nothing slips.

I've tried a few some different brands for that kind of thing. Found one that fits me well and comfortably and have stuck with them (enfemme, but I suspect it's partly just normal variation in humans that leads to some people loving the other brands I tried). I didn't experience any discomfort normally and I tucked basically all-day (not night usually) everyday for about a year before starting HRT (I probably have a high threshold for pain tho). Never tried tape.

The ones that happen to fit just barely loose enough to have a nut pop out are the worse. I've gotten better with technique over time, but if they don't fit right, it's not gonna work well ime.

I am going to ask a really silly question: Have you tried using a panty liner? (yes, the period product!) They tend to make panties a little more structured while still allowing for natural movement, and I assume it will help with a gaff too

What worked well for me early in my transition was sizing down my underwear. If I wear a medium I would wear a small, and that helped a lot. When I want things to be completely smooth down there I wear a gaff, leolines on Etsy aren’t cheap but they’re really the best I’ve owned. If you go with a gaff try find something in cotton it breathes and wicks away sweat.

I wear a tucking gaff under tight pants every day. I'm above-average size and have had the sack skin falling out issue too. Generally with tucking you want your balls pushed up into those little pockets in your upper pubic area, where they were before they descended. It'll get easier over time as your balls shrink if you're on HRT. Mine just chill out there on their own a lot of the time now after a little over a year on HRT.

This is how I do it: First, put on the gaff loosely and position the front lower than you think it should be. This is so you can hike up the sides and the back to keep it tight later. It also helps keep the sack skin contained since the gaff will be positioned to be wider further down. After that, grab the head of your penis from behind, arm behind your back and reaching between your legs, reaching into the gaff, and pull your penis back between your legs, so that the head is almost to your asshole. Don't pull your penis too too far back or it'll be painful later. Pull up the gaff, tight so the penis stays in place, with sides and back going pretty high up to keep it tight. The gaff needs to be tight! The gaff should keep your balls up in those pockets and your penis tucked under without it slipping forward.

I use BBLAIR tucking gaffs in XS size with my 36 inch hips and 29 inch waist. (For me at least, I buy bottoms based more on hip measurement rather than waist, since my hips are a lot narrower than most cis women's, or at least typical women's pants.)

I use two pices of mens underware and a bit tighter pants(usually for womens pants because the dont have that bulge space) and it works pretty well actually. I really struggled before, but that seems to do the trick for about 80-95% of the time