If I am going to be totally honest with you the best way to keep a secret is to tell no one. Not even   your best friend. And I am not cynical by nature, but I say this for 2 reasons. I can't tell you how many times one of my closest friends has let my secret slip in a moment of anger or fear or something of that sort. And 2 I have leaked my fair share secrets as well ( I am sure you have too), and it didn't mean that I don't love my friends, but you know what? circumstances arise and you have to make decisions and sometimes it just happens in the spur of the moment. And If you and I have done it, then who's to say your best friend won't too?

If you REALLY want to tell someone though, I suggest you tell someone on the internet. To be honest before @catastrophiiic (amazing hooman) I wasn't fond of the whole internet friend thing but telling someone on the other side of the country your secrets means that it will stay on THAT side of the country. I don't care if John in the Bahamas knows that I have a wart on my big toe (It was a joke) But I DO care if my John from my school knows that. You Know?

It keeps you happy and away from disastrous situations, unless of course John from the Bahamas and John from my school are in a long distance relationship called John^2 and tell each other everything, in which case...oops.

-Lesson of the Story: Better lock it in you pocket, taking this one to the grave. (Fandom reference, 10 hugs if you know it)