How do I break down a guys wall?

Okay so a few months ago I met this guy, he is super sweet and we have a lot in common but there is one problem. His past relationship went really bad from what I heard and now he's sceptical when it comes to either love or relationships ( heartbreak I assume ) . When we first met we both got drunk and all cuddly but the second time he was more reserved ( we walked through a forest and afterwards got two drinks but he went home early ). Now we are chatting daily and it's really nice but I don't know how to bring this to the next stage and should I even try to do it?
If anyone can give me tips on how to break a guys shell?
How do I break down a guys wall?
Add Opinion