The moment you start doing Tarot readings for others, you are going to encounter issues with ethics. It is best to think about this before the event rather than creating uncomfortable situations for yourself and your clients.

Do you hold very strong opinions on certain moral issues, such as homosexuality, abortion, or adultery? If so, how are you going to handle them when they come up in the course of a reading - as they inevitably will. Are you going to try to remain impartial and non judgemental, or admit to your client that it might be hard for you not to make your own opinions known?

What questions do you regard as permissible? Are there any areas that are off limits? Would you do a death prediction, for example? There are many readers who feel that such predictions are unethical, yet others seem quite happy to do them.

How far is it permissible for a client to ask about others? Is it alright to use a reading like a "psychic spy camera" or is this an invasion of the privacy of another person? Do parents have the right to information about their children?

There are no right and wrong answers to any of these quesions. You will have to negotiate your own way through them. But a good reader is one who has thought about such things in advance so their readings are not compromised by them when they arise. And as a client, these are good questions to ask a potential reader.