In my case, I’ve always gotten a pen and paper, and proceeded to break down what ever this program, script, or function needs to do into its fundamental components. Followed by writing down the general structure for how it needs to do so for my application. That’s when I prototype in actual code. My reason for taking such a round about approach is whenever I attempt to go straight to the prototyping stage, I find myself needing to do constant rewrites and refactoring of my code to achieve the desired result. I hope this helps comrade.

I’m not a professional programmer with formal education or anything like that, but for me writing software is sort of like painting a picture; First I think of what I want the program to do and imagine how it should look like, a basic structure. Then I start hacking towards this goal, just to get it working. At that point I usually have a basic skeleton of a program that can at least do a bare minimum. After that I usually start doing things like thinking of adding more features. One feature at a time, step by step, keep things simple. I always found this to be the best way for me personally.