I seem to remember that with day time naps I started out taking them out for a walk in the buggy at set times during the day as they would always fall asleep eventually when the buggy was moving. It did involve walking for miles sometimes to get them both off but after a few days we started to get into a pattern so they would expect to nap at a certain time. At around 5 months old I then used Pick up, put down to get them to nap in their cots. Basically put them both down at the same time, then when one cries, pick them up, soothe, then put down again as soon as the crying stops. Repeat this process until they finally fall asleep. You stay in the room the whole time. There's lots more detailed information about doing PUPD on the Baby Whisperer website.
Now I admit that this was very hard work -running back and forth between cots- for a few days as you can't tend to two babies at the same time. I actually think this meant that the babies learnt to self settle quite quickly because I couldn't always respond immediately to one if there were two babies crying at once. During this time, I also discovered that white noise helped my DD to drop off so I started playing it every naptime. I also played the same lullaby cd pre-nap as I did at bed time and blacked out the room. I think it took four or five days, but in the end, it worked. For my two, making sure that they weren't overtired was really important too, otherwise one would just wake up after 20min, cry and wake the other, so I watched very carefully for sleep cues and got them down asap. I hope that some of this helps. Good luck.
I have a query re twins sleeping patterns during the day. I am very lucky in that my 6 month old b/g twins go down to bed at 7pm every night and dont wake until 5-5.30 the next morning...however, Im struggling to get them to sleep for naps during the day. When one falls asleep the other wakes and vice versa....does anyone have any tips on how to get their naps in sync? They feed at the same times during the day but just will not sleep at the same time...am I being unrealistic to think that this is possible? Should I just be leaving the non sleepy one in their cot to cry if the sleepy one is in their cot....eek...all a bit new Im afraid! Any advice would eb very welcome!