Gradual retreat....I'm a little confused

[littlestressy]

My DS has been in hospital recovering from an accident, he's on the mend now (yippee!!) and I feel ready to sleep without my help.
While in hospital I would do whatever it took to help him sleep, generally bf or sleeping with me. He's 15mo so I know he doesn't need night feeds anymore, he was night weaned for months before his accident.
Previously I have used CC to help him learn how to settle, but after his accident I want a gentler approach so am trying gradual retreat....at which I know nothing so I have some silly questions:
Can I read/use internet on phone in his darkened room while he is settling?
At what point do you leave the room?In a deep sleep or just fallen asleep?
Is it ok to talk to him to calm him? Like "lie down go to sleep"
What do you do if you are meant to be on other side of room and they just won't settle?can you move nearer to help them? Because atm he really wants to be touching me.
I know these sound like stupid questions but I think I've become a bit precious about my DS!!!!
Thanks anyone who can help

This is useful, btwiki.ebrey.net/index.php?title=Sleep_Training_-_Gradual_Retreat

We did this with DD, I read to myself while she was sleeping. We had a cushion which was the sleep cushion on which I sat and was moved closer to the doorr every three days until out of the landing, too about a week to get out of the room. You stay with them until they are asleep and for about 10 minutes longer until they are in a really deep sleep. No talking because you are in the room so they should be calm with your presence.

Thank you Five I have worn a spot in the carpet by the cot, need to move I think!
sharond that link is brilliant, think I need to move on a stage, great help thank you.