It's something you will get used to over time. I hold my hood at about my stomach and then drop it and it closes everytime. Where you hold it also largely depends upon your height too. It may be difficult for someone under 5' to hold it at their stomach!

Actually, I have a funny off topic, but S2000 hood related story that happened to me. It was after I installed my AEM CAI. It was a cool fall day. There was slight breeze.I was taking it on a test drive and after a few minutes I got a check engine light. So I pulled in to a parking lot to check it out. I poped the hood up started looking around in the engine bay. All of a sudden we get a small gust of wind(nothing too strong), and the hood fly back against the windshield frame!!! I grab it quickly and examine it. There was no damage to the frame, windshield or hood, but it sure as hell freaked me out. I haven't had that happen since then, but I don't think I'll ever forget it.

-Brandon

 

Less than a foot works for me.
At the dealership after looking at the engine, I went ot close it and the guy said, "No there's a certain way to do it."
He then proceeded to drop it from the very top, as if it was necessary.