“Foal to 5 years” is a book I found very useful when I bought a youngster, who was further along than yours. Patience, with firmness is paramount. 18 years later I am still dealing with the mistakes of my one horse’s initial owner who thought it was “cute” for him to chew on them. He only tries maybe once a year, but I can never trust he won’t, so I still have to tell anyone new around him that he may try. Good luck with your baby, and remember to get him to allow his feet to be handled ASAP. You said “colt,” if you are inexperienced you may want to get him gelded, will make your life easier if you are not used to handling stallions. He will be starting to get the testosterone thing gong on soon.