I think we all know what a guy would want other than that try a nice dinner maybe a little gift like cologne a walk on the beach & that's pretty much it you could try a watch concert tickets etc I'd say stick with the dinner & from there do what ever makes you two happy
Men are all different and may want varying things on the day and their likes and personalities also play a big part in this. There are those who would prefer the day to pass with no notice while there are others who would to have a romantic date with their partner. Most men are easy on it and a nice homemade meal would be a great way to spend time. You could get him a small gift like a watch or something he likes and that would make his day.