VG/PG ratio is one of those things that sounds technical but is really about your personal preference. Do you want huge clouds? Go high VG. Do you want a strong throat hit? Go higher PG. Do you want a middle ground? Start at 70/30 and adjust from there.

If you're mixing your own, don't do the math by hand. Use the Windbar E-liquid Mix Calculator to nail your ratio every time. It takes five seconds and saves you from a batch of juice that's too harsh or too weak.

The bottom line: know what the numbers mean, adjust to your taste, and measure carefully. That's the whole game.