Ok, routine for sleep is:
Nap time (sling) - kiss, tuck head in.
Nap time (cot) - clean nappy, sleeping bag, cuddle, lie down awake, dummy. I kind of hold the dummy in with the heel of my hand and stroke his forehead. If he cries I put my cheek right next to his and shh. If he cries with that I pat his chest. If he still cries (this hardly ever happens) I pick him up and cuddle him til he stops crying and looks drowsy then put him down awake again.
Bedtime is the usual plus a last feed on my bed. If I have timed it well he will not fall asleep but he often does. I wake him, sing him a little song and put him down as for a nap. Last night he was wide awake, I had to go to the twins and when I came back he was asleep, dummy was nowhere to be seen. So he can do it!!
To extend his nap today I went upstairs at 30 mins in case he was OT. At 45 he started writhing around so I popped the dummy back in, covered his eyes, shhd. I did that for 15 mins - he kept looking like he was asleep then waking again - this is what he does during his long NW too. In the end one of the twins started shouting for me at the stairgate and then I had to go and he woke up. I remember extending naps with the twins but this is what I did with them and I think it worked most of the time!