There are a few ways to go about this. I prefer the first one:
-Send an attachment via email and have the client print it, sign it, scan it and email it back to you.
-Send it to them via regular mail (it takes longer but it’s also effective).
-Send the client a copy of your waiver (and/or any other document you need them to sign) and after reading it and agreeing with it, the client can reply back to you via email saying that he/she agrees with everything on the documents you require them to agree on.
As for your second question, you can schedule a time to connect with them to go over what ever rules, goals, etc. even before you start training them. After you both agree that this will work then schedule your first session and go from there. Feel free to message me with more questions if you like. Good luck!