I believe give it to him before, it's still a surprise and that's very spontaneous of you and most men love spontaneous.I remember we were going to a wedding, being a distance person getting married my wife bought matching black lace panties and matching lace stay-ups for us to wear. It was very fortunate that she bought me the wrong size stay-ups and they ripped when I put them on. It was fortunate they ripped because at the wedding I met some old high school friends and one of the girls got me on the dance floor and the DJ was doing a intro to a song and asked all the women on the dance floor to pull up the men's pants up to there knees. Wow that would have been interesting, after the dance and we were walking off and she told I didn't strike her as one to shave my legs and she couldn't believe how smooth my legs were. Well under that situation, I thanked her. When I went back to my wife she was laughing and told me how lucky I was the stay-ups ripped.
Have fun at the party and I'm sure he's going to enjoy your gifts.