how should I tell him I want to try for a baby

Shannon
Hi ladies, I'm currently 19 years old my parter is 22 and we've been together for around 3 years. 
A lot of our friends are parents or are expecting and I feel as I've I want to talk to him about possibly starting our own family. I'm scared of his reaction as it's something we have never clearly spoken about and wondered if you had any advice! 
Thankyou !!!:)