I use graph paper
But ive never heard of mine draft
You can use design software to do it but its harder to do in my opinion. Better to build it as you go as this allows room for new inspirations and vast improvements
I use a client hack that allows you to fly, on Minecraft Classic not on survival.
Some minecraft classic servers allow the fly hack.
Or some simple rough calculations. Take some dimensions of your project.
All of my creations are spontaneous and unplanned. BAFI included. By unplanned, I mean that I don't draft them or even draw a rough sketch before I start working. I do, however, spend many hours thinking of how I'll do it.
Don't worry, Minecraft.net and the bukkit forums are all cool.
We just frown upon links to dubious/ illegal/ other servers websites.
the ASA building was designed in 10minutes using paint and a blueprint of round shapes ranging with a diameter from 3 to 31.
paint is nice once you learn how to implement it in minecraft. 2d images are also easier to grasp (and think in 3d) than 3d images imo.