Advice...

I really don't have anyone to talk to or ask about this, so I was hoping you ladies could give me some advice on something. How would you come to your SO about a money situation...I'm a stay at home mom and he works full time and makes around 480 weekly. We pay our bills on time and get everything my daughter needs, but after that is done he suddenly has no money because he eats fast food 5 days a week instead of taking a lunch and idk what else. I'm not included in any financial dealings. I get he works for that money and it's his, but at the same time we have no money put back in case anything happens and we have another baby on the way. All I want is to be included and write us out a budget and start working on saving money in case we need something or something g happens. I just don't know how to properly approach the situation.