I think I've inadvertently sleep trained my LO for naps.
He used to nap on me most of the time but it got to a point I was sick of being stuck on the sofa and it was becoming more of a fight every nap time.
So I started putting him in his snuzpod in the living room with his dummy, a comforter, a blanket and the white noise on.
At first it took anywhere between 10 and 40 minutes for him to fall asleep but at least I wasn't getting kicked and scratched and stressed out as I could step back whenever and take a breath.
He's now taking naps in his snuzpod in our room and for a while I've been putting him down and leaving him. He generally falls asleep on his own now, unless he's overtired.
Even if he cries/moans a bit he's usually
asleep in under ten minutes. I just found if I was there putting the dummy back in and patting him etc it just went on forever, he almost played up knowing I was there and wasn't picking him up. So I'd leave him, let him cry for a few minutes (didn't time it, just judged it myself and went back when he either got too upset or it felt like long enough) and gave back dummy, tucked him in, and repeated until the final visit he was so tired he'd take the dummy and fall asleep.
Sleep training doesn't have to be leaving them to scream for hours etc. I lots always horrible hearing them cry but if it works then in the long run I think a little bit of crying is worth it if it improves their sleep. A baby that's slept well is always happier!