Dd also recently transitioned to a single bed (at about the same age as your lo)... We had the bed in her room for a few weeks before moving her in there. Then one night, she was sick, so I ended up sleeping in the bed with her, so I thought "Right, let's just get her in the bed now!". So the next night we put her to bed in the bed, and it was fine. It is a very low bed, and she can easily get in and out herself, but doesn't really tend to at night (it's the darkness I think). I kept her in her cot for her nap for about 10 more days and then took it out of her room, and put her in the bed for naps as well. It took a while for the novelty factor to wear off (getting out of bed at nap time and playing) but I think overall we have been very lucky with our transition.
Good luck!