General approach in Japan
Many thanks to the posters of this board, TravelerX and others. Sharing your misses (or missus if you're into that) is as helpful as the success stories.
I speak Japanese at a high-intermediate level, and am in my mid-60's but look younger. Thought I'd share some additional insights / thoughts.
Keys:
1. Be unfailingly polite. You have 2 strikes against you as a foreigner, especially if you aren't white. Be the perfect respectful, clean, safe customer and doors (and legs) will open. Act like a Karen / Kevin and you ruin your chances.
2. Make sure you understand pricing. There are taxes / surcharges but if it's 10%, don't sweat it. It's the surprise doubling / insane charges to watch out for. Deriheru can't advertise sex (AF is almost a sure thing though) and no one owes it to you but if you are clean, respectful, fun, and give safe vibes, 10-20 k yen more will usually do the trick.
3. Once you've paid or gained entry, act like you belong because you do. You are the customer and the customer is a god. If you don't like a girl, ask for another or don't buy her a drink.
Connection matters. Learn to use translation apps effectively. Have some phrases saved that you can copy / paste. Learn to use spoken translation apps as well as typing can be slow. Many Japanese understand if you use short, simple phrases. It's the 'um, well, I guess you could say' verbal noise that confuses them. If you can quickly share about you, your job, hobbies, birthday / blood type, fav foods, etc. You'll connect more quickly. If you're still sharing birthdays at the 20 min mark, you've run out of time.
4. Don't be afraid of failing. Talk to every woman you like. They're used to it and not offended if you are polite. But talk to everyone around her as well, guys included. Singling her out immediately is rude and not effective. Gaijin have the rep as players. Don't obviously be one but you can still be efficient and focused. That said, 'Don't chase the night. " If it's 1:30 am, you're sobering up from being drunk and struck out, just go home and beat off if you need to. Trying to find that perfect experience isn't likely to happen and you could lose a lot of money and sleep and still be frustrated.
5. Be direct once you've established a connection. This is with escorts, massage ladies, in the wild. "You're so pretty. I like you. I want to see you later / tomorrow." If they decline, bow dramatically (make them laugh) and wish them the best. It's usually better to get their LINE # and connect later / the next day as women don't want to be seen as easy / loose, especially with gaijin. You can sometimes close the deal immediately but it will usually backfire. Give some cover / deniability. Language exchange, tour guide, share a fav food, then bang. I've gotten BBJ, FS, dates from legit massage ladies (not always at the time but later) by just asking. The main thing is they need to trust you as they are often risking their jobs by doing more.
MISC:
* Japanese women don't see sex as dirty or shameful. It's a basic bodily function. They often put on the 'shy / innocent but you are such a sex god that they can't help themselves' act but some will be refreshingly forward.
* You may get newbies who are genuinely nervous but those can end up being the best experiences if you are patient, kind, and know what you are doing. If you get them horny enough, almost anything goes. Compliment freely. The worst is the ones who don't want to be there and don't care. Generally the hotter ones who know it. They don't last. Share you are disappointed at the lack of effort and cut the session short. Sometimes they'll at least try then. Give feedback to the scheduler / site.
* You can do a ton of research and pay a premium for diamond level / PSE which is great if you have the funds or limited time. I far prefer a high volume / cut bait approach as it's low risk / cost in general. Oppai clubs, DeriHeru, etc. Are good experiences even if you don't orgasm. Enjoy the variety, boobs, great skin, kissing, and even cuddling / affection. I've turned cold / disinterested / jaded partners into discounted OTC visitors once they feel seen / heard / respected and cherished. Don't fall in love but you can show that you are genuinely interested in them as people, listen well, and hope they thrive.
* Japanese women give the best BJs for what I like. Slow, sensual, a lot of tongue / mouth contact and they try to make it last. I don't like sloppy toppy / PSE style. Sex is wonderful but a good BJ w / CIM can be more satisfying. Mix it up.
* Bring little gifts if you return to a spot. Giving a few beers, chocolates, snacks to manzoku and providers while remembering their names does wonders. Tipping can backfire but gift giving? There's nothing more Japanese.