How to tell when you're ovulating

So, ladies, my roommate and I were talking the other day and she shared some pretty interesting stuff with me about how to tell when you are ovulating. The key is to check your temperature with a digital thermometer every morning, before you take a drink, or get up to pee or anything..so, say your average temp is 97.9 and the day that it goes up, noticably, say to 98.6, that's when you are ovulating. It takes a day, but it's very safe just to say 3. so For those 3 days, that's when it gets white and mucousy down there, very slippery, so it's nice and easy for the sperm to slide on up..but we don't usually want that to happen, so..it's good to be aware that sperm can live in the body for up to 5 days! yes, 5 days..that's a pretty long time. so anyway, if you're temperature stays up forever, you're pregnant, but when it drops back down, you'd better go grab yourself a tampon. It usually is 2 weeks from the time you start ovulating, to the time when you're temperature drops, you're period time. now, I haven't quite figured out the exact timing it's safer to have sex without getting pregnant, it is still pretty risky though. anyway, just thought I'd pass along the info for all of you who don't know.
If anyone has any more information about how to tell when you're ovulating, feel free to jump in and inform me!