Sleep training

Anyone start sleep training their babies. We recently did extinction at night, he cried for max 20 mins the first night and less and less as the nights went on. So now I’ve decided to start naps, since he is a 20 min in your arm napper🙄 we are on day 2 and it’s going a little rough lol I also did this with my daughter but don’t really remember how it went or how long it took. Basically I’m wondering how long nap training took in your experience and if you’re in the middle of it, how it’s going. Thanks!