The easiest way is crafting dhide bodies. You lose a lot of cash, but it's good speed, and very straightforward. With herblore, it's hell. I've been calculating ways to get 82, and there's nothing easy. Potion prices fluctuate so much, there's a huge risk. I personally just spent 15m on harralander tar ingredients, made them all, and in that time they dropped from 260 each to 210 each. And I have 80k of them. And that was only from 67-73 herb.