2. If no one is around stat with super low dose first time. And grow from there over months if you are scared. You'll understand after low dose what's coming and thank yourself later.
2. You can not have any and I mean any plans for that day. Not even I'll have to take the trash out in the evening, seriously. Turn the phone to airplane so no one can call and block messages. You do not want anything that requires functioning human from you. You could do that but it will ruin your time.
4. Outside - no matter how cozy your home is do it in your country house or somewhere where you are alone and feel safe, have a fallback house or place but still in nature. Dunno, rent something.
They're not ideal, but better than nothing.
Even better would be to start making friends in the psychedelic community -- which is getting easier to do all the time, and to maybe find an underground guide. Another way to go is to sign up for a research study.