How do I get pregnant ?

So I’m currently hooking up with this guy, we have an agreement… I came up with the whole idea that we should be sex partners and keep our relationship casual no strings attached. He just came out of a toxic marriage where his wife cheated and so have I with my husband. My thing is I want a baby by him. We currently do not use protection, so question is how can I get him to cum in me? We use the pull out method.