Those all are good methods! I know the best way that worked for me was close to Jeanie's way but a different symbol. However, where I read it was always the : was representing the boy, or so I thought.
Female ;
Male :
That's how I've seen on several websites when I was accurately trying to tell whether Tevy was a boy or a girl. I guess those probably don't work too well so I'll explain how I was told.

Take the kitten in one of your hands, having it's head facing away from you and it's behind facing you. Now, if you can get it to stay still, lift up his/her tail and take a look. It took me many times to do this before I was almost sure that Tevy was a girl. On a female you would generally see a verticle slit pretty close under her bottom's hole. In a male, I've heard it's more of a round hole instead of a slit below their bottom's hole, and the holes would be spaced more apart. (don't forget that on either side their might be buldges, that would likely be a boy because it would be his ahem.

)
That's the best way I can explain how I was told, if I was told wrong then maybe I really don't know what Tevy is. Although I'm 90% sure Tevy is a female. It's a good thing though, if Tevy wasn't, her name is either or I believe. HAHA Anyway, have a good day and good luck with your kitten, I hope you tell us what it is! Your question was not stuipid either. It can be hard to tell the sex of the kittens when they are little if you don't know what to look for. I even had trouble since Tevy was the first little kitten I ever had to sex.

Once again, good luck and I hope I helped and didn't confuse you more.
- Randy