I think that huffing method is pointless and weaker. It's not a bag of glue, it's a gas. Breathing into the balloon leaves moisture which can freeze and weaken the balloon. Also if someone's sick they can easily spread what they have if the balloon is shared.
Holding it gives a longer time for the nitrous to be absorbed. I hold it for about 10-20 seconds. There's still some N2O left after so I blow it back into a balloon for another weaker hit. The third hit still has a little bit left but it's almost not worth it and anything after is pointless.I know with the first couple uses or so the balloon is pretty rigid, it needs to stretch out a little. No offense, but maybe you lung strength isn't that good. Maybe you should breath with your diaphragm, cut back on smoking, do some cardio or yoga, if you don't already do any of these already. It isn't like tripping on acid or the media portrayal of a trip, but shit will seem different. It gets kind of blurry, a little distorted visually, not like acid, but you should have auditory effects like "wa wa wa" and trippy mindset with euphoria and a sense of deja-vu.It only takes me one 8 gram charger. That's the most my poor lungs can hold. Some athletic individuals can hold 2-3 chargers at once. Wise I had those lungs

.They try in vain and end up going through a case of whippets. You can fill the balloon with more than one whippet. Just fill the first hit, pinch or twist the balloon shut to hold the N2O in, load a hit, screw up, release balloon, crack, and repeat if desired. You can also use a whip cream or soda dispenser to load more whippets. Although they have a pressure release valve that makes you lose anywhere from a little to a lot of N20, depending on the size, make, and number of chargers used. More chargers=more N2O released out to the air. But at the same time the greater pressure the N2O is under seems to make it more potent than a balloon.B12 requires an absorption factor in the gut that can only absorb so much B12. After a certain amount the B12 absorption factor gets overwhelmed and the rest is wasted. Some have claimed that sublingually or mega doses may overcome the limitation of the b12 factor, but AFAIK the only way that's proven to get it into the system in higher doses is from injection or sprayed into the nose. Methionine, folic acid and B6 might also be helpful, especially the methionine. I wonder if the more common SAMe could be used in place of methionine?
Even if you take all that shit, I don't think it's proven to prevent b12 deficiency induced by current N2O use. I've read about using injected B12, sometimes with methionine, to treat a patient suffering from nitrous-induced b12 deficiency after they stopped using in the hospital, but not during. The problem is the nitrous oxidizes the B12. It's there, just useless. What I wondered is that even if you shot up b12 twice a day would the new b12 just get destroyed?