Im still a virgin and I’m gonna get deflowered by a big guy, any tips?

I met him on The blowers and originally I only wanted to suck him off but he said he only meets up if more happens so I told him if we keep it slow I’m willing to let him fuck me. Getting deflowered is not necessarily the thing I’m scared of but him being big (7 inches). How do I prepare? I mean I have a dildo but I can’t even get that inside of me.