When do we start disciplining our kids? And what method is good? My baby is going to be 9 months. Is it too early?

It never be too early as most of us talk and read story to baby during pregnancy. Also it can promote their focus and interest in book. Different stage got different book. Likewise for newborn they are encourage to give black/white pictures book as their vision only able to see b/w. Early stage story mostly are pictures and accompany with puppet. As for 9 month you can prepare those fabric book as they are teething now thus they tend to bite