Okay, we're not going to sponsor any effort of writing a note here. Sorry man, but we generally prefer living people. And no problem about talking...anytime. I understand that you feel like it's calling you, but how long have you felt that? Are you sober right now?
Knowing it's not the right thing to do is a good sign. It's calling to you, but you know it's not the right thing to do. But man, this isn't a cookie jar. This is your life.
How about this...have you read the first post in this thread? If not, please go back and read it and think about it for a few minutes. And before you take any dangerous actions, actually read more pages from this thread as well.
Trust me, all of these dozens and dozens of people feel/felt the same way as you. But they're still here. And you can be too.
Think about the things you want to do, but you have not yet. Travel? Get your dream job? Go on a date with your crush? Write them out and think about them. If you give yourself the chance to keep living, you give yourself the chance to possibly make these into realities. I promise.