1. Don't mention anything remotely resembling escorting, meeting up, privates, or any other clever term you think gets around censors or regulations on OF. They have a strict policy about it and getting both your accounts flagged is not the way to getting on her good side lol.
2. Tipping does nothing. If they know they can get generous tips and gifts from you for nothing, they won't ever meet you.
3. A live video chat is about the best way, although it can get expensive quickly due to number of chats you might book with a particular girl or several. If they're UTR it might take a few chats for them to get comfortable enough for you to ask. I certainly wouldn't suggest booking a chat then asking 30 seconds in. If you know they provide but you just want to try direct you can probably get there faster. If you're picking up a good vibe (1st call or otherwise), ask for an email or some other outside of OF method of communicate where you can contact them. Ask how she feels about a meeting there.
4. Don't try to be clever and ask to "content trade" with them if you're not actually a well established talent. That gets their creep radar up.
5. Most of the time they don't run their own accounts so they won't know it's you. If you're not live video chatting assume you're not talking to them. I wouldn't trust any kind of text or dm service they offer.