Please give advice-Sleep training

I am looking forward for advice from you mommas on how did you sleep train your babies, what method did you use and how long did it take to succeed? My baby is 4 months old and his sleep schedule is chaos, since we fought with terrible colicks and now teething crisis.

I know at 4 months we go through sleep regression, but i couldn't make a schedule even before. And he sleeps only after i nurse him, he is EBF. I would love if both me and my husband can put him to bed and fall asleep on his own.

Thank you so much in advance!