How to send an invitation message to members of a massage parlor?

I think it's similar to an ordinary invitation. First of all, it is a title and the most cordial. After all, it is an invitation. Then there is the purpose of the invitation, which should be clearly stated, such as: who is there at the time and place, why, what to bring, what to do and so on. Finally, there are some pleasantries, such as "I hope you arrive on time" and so on. That's all, I hope it will help you a little.