We don't even have to sleep train at nights, he's so exhausted and stuffed he just falls into bed! Just put him down for his 2nd nap, I find if I go and check too frequently or try to calm him, it just makes it worse. So I put on his musical toy and gave him his blanket and he has a couple of soft toys in the crib with him and left him for 10 mins. At the end of the 10 mins, I could tell he was really winding down and within a minute or two, he was sound. He has such a great night time routine that we've been doing for about 4 months and I hope after a few days of him getting used to a naptime routine, it'll be easier. Currently he nap-nurses on me and even though I love it, I know he needs to sleep in his bed and when he goes to a childminder or a nursery, there's no way they will do that. I could never just leave him for hrs like some people do. At the end of the 10 mins, if he wasn't winding down or showing signs of being ready to sleep, I'd pick him up and spend 20 mins upstairs reading or playing quietly then try again.