Unless you have major issues during the transition, then I don't think you need a prize.
For me us, I just slowly changed things, much like you would transition from breast milk to formula, or formula to milk... you change the amounts. :)
Instead of 100% mommy lies in bed until he falls asleep, and 0% he's alone before falling asleep, you change the percentages... gradually. Mommy lies with him in bed (or on the bed, whatever you do) for 90% of the time, and then gets up (I always had a "reason"--like, I needed to empty the dishwasher, or I needed to fold the clothes from the dryer). So the last 10% of the time you are gone doing whatever, and he is alone (but can hear you doing things, so he has that assurance that you are near).
After a day or two, you up the percentage of alone time, say to maybe 80/20. Then after a few days of that, you make it 50/50. After a week or so of that, you go 25/75... and then you say, I will lie here with you for 2 minutes, and then I have to go out so you can go to sleep. (no arguing, no carefulness that you don't want to upset him, not accidentally asking him if he is ok with that--- you just tell him that matter-of-factly). And then you stick there for a long, long while.
What is 2, 3 minutes? You'll miss that one day. And one day, you will just walk out after kisses and good nights and not even think about lying down, and he will be fine. And that will become the new normal very quickly.
Know up front, that you may not get "relief" from that last 2 minutes for a few years yet... (unless you really want to force that, too)... but it is kinda nice, really. Count in your head to 120 or 150, slowly, and do not let yourself fall asleep, or be talked into staying longer. You must be consistent. I did it this way when my son was 3, and he adjusted just fine. We still read bedtime stories until he was probably 5th grade, though. :)
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Gidget, I totally forgot, but I did that, too! (telling him I would come back in a few minutes to check on him, and then making sure to follow through, for that trust thing. :) And like you, even after he stopped "needing" me to do that, if I SAID I was coming to check on him, I did, even if I knew he was asleep.)