So, lets attak this in two parts. (assuming u mean mid - long term)
1rst if u just met:
- List of limits, soft and hard
- List of preferred things to do, wether is vanilla or not that vanilla.
- Set schedule for playing times or regular interaction.
2nd if u already know eachother to a certain level
- Getting to know each other better.
- Getting a token that ressembles your partner / show beloging without everyone else noticing, it could be anything, the most usual thing that comes to mind its (for women) a tight neck black ribbon, but it can be anything... like a hair pin, earing, hair tie used as a bracelet, an specific color clothes or even a lego toy.
- A taks system, consesual as always, with rewards and punishments
- Voicechats or camchats, depending on preferecnes and techical possibilities.
Theres probably more things but i cant think of more right now, hope being helpfull