Your technique will improve over time, meaning you will waste less. I like to fold a V-groove in the foil, and keep the flame of the lighter somewhere behind the beetle, so it is always moving into a colder spot. That minimises the probability of a frazzle. At the end of your toke, you can release and re-depress the trigger on your lighter (assuming it's a flint one and not a piezo one) to spray unburned gas on the foil; this will cool it and help the beetle solidify.
But be warned ..... It's only fun a finite number of times.
The definition of a habit, I have discovered, is when you are taking drugs purely to avoid the comedown.
As you can tell from my not enthusing wildly over how wonderful heroin can be, I am currently taking a break from the stuff (ran out on Tuesday, though that was really just the last of a bonus beetle; the main binge was last Saturday). Casualty is not on tonight, so I couldn't play my usual Casualty game (where I take a toot every time someone mentions "ten of morphine", double if it's Zoë because Sunetra Sarker) even if I did go and score. Which would also (1) cost me money I cannot afford, (2) mean that all the suffering I have been through the past few days and nights would have to be gone through again eventually and (3) not go at all well with my PiC, whom I have no desire to lose. Also (4) I absolutely have to be straight tomorrow.