Hi Adele,
Going to a 3hr routine will be a lot of work, but it was definately worth it for us in the end. You'll end up with 3 good naps and nighttime so you can have lots of YOU time:)
In the beginning you need to really stick to the routine, so don't go off by more than 1/2 an hour in either direction. Which means you have to wake him up when it's time to EAT, otherwise he'll never learn the routine.
On the first day, I would start out by giving your normal 4:30 or 5:00am feed and then straight back to bed as usual and then give next feed around 7:30 and start the 3 hour EASY. Here's what I suggest for your first day:
4:30-5:00 feed with lights off, no talking and straight back to bed
START EASY HERE
7:30 feed, activity
8:30 nap 1 (1.5 hrs) (try to stretch this to 9 in a few days)
10:30 feed, activity
12:00 nap 2 (1.5 hrs)
1:30 feed, activity
3:00 nap 3 (45mins-1.5 hrs)
4:30 feed, activity
6:30 feed and bed
10:00 df
Then for the next days, I would try and eliminate that 4:30-5:00 feed by decreasing the amount or time bf. So that maybe in a few days he first wakes closer to 6:00, then I would start the EASY at 6:00 so he'll go to bed a bit early for a few days but then you can slowly keep him up a bit longer at night so that he'll wake a bit later in the morning.
Hope I haven't confused you, let me know if you have any more questions. Tarri