ah yes, happiness is a beautiful, beautiful thing. For me personally I find the easiest way to be happy is to stay true to yourself and have those closest to you be able to accept, nay, even celebrate that. For that you need
A. Freedom
B. Protection (naw, I'm just making an obnoxious joke
. what I really mean is "friends and loved ones"
That aside, I don't really think you can have something like perpetual happiness. While it may just have to do with our biological hormones simply "running out of happiness juice", I prefer to think that it's because of mankind's innate desire to get more than they have. (I think it applies to most of life on earth. If you grab a dog treat out of a bag, and offer it to Roofus, he'd sooner jump for the bag of treats than the mere pittance you're offering). No one is happy 100% of the time, even if they follow the "happiness formula" to a tee.
I'd say "rather than shoot for perpetual bliss, try to be honest: to those around you, and to yourself. At least that way you can be content".
...but of course all of this assumes there aren't people out there who actively make your life a living hell. If that starts happening, well, you've got to get a little pro-active yourself (and hey, face it, it gives you some motivation!)
...yeah, life rocks.