Offline is easiest. Online is not possible using Office 365. I haven
Email only used for tracking and contact purposes for emergencies and things of that sort. I can do it this way in theory, but I've never had to, so I can't say for certain. I like to write in person, rather than digitally. My experience with this is, you can either get the email, or you can get the physical mailing package, but you can't get both! :p I'll address the first one in detail: Your email will go to your inbox. So you get to keep it and read it whenever you want, as many times as you wish! :) I was so delighted about this that I got to type it up, and I'm making sure it's easy to find for others who may be trying this method. The good news is that you can do it in the middle of a project, with work still going.