How to test a fragrance properly.

Perfume retail is set up to make you fail. The lights are warm, the air is full of forty other scents, the salesperson is timing you, and you have ten minutes before you have to make a decision. Almost every perfume you ever regretted was bought under conditions designed to optimize for anything but whether you'd actually wear it.

Here's a more careful way.

Don't buy at the counter. Ever.

Sample. Always sample. A 2 ml decant costs four dollars. A 50 ml bottle costs a hundred and fifty. The math is unforgivable.

If a counter doesn't offer samples, ask anyway — most do, they just don't advertise. If they refuse, leave. The houses that won't part with 1 ml of their fluid are not houses you should be giving 50 ml of money to.

Test on skin, not on paper.

Paper strips ("blotters," "mouillettes") are useful for comparing a dozen perfumes in a row when you're trying to narrow a list. They are not useful for deciding whether a perfume is right for you.

Perfume reacts with your skin chemistry — your pH, your sebum, the residue of whatever soap you used this morning. Two people wearing the same perfume can smell startlingly different from each other; the same perfume on the same person can smell different at the gym than at dinner. Paper tells you what the perfume is in the abstract. Your skin tells you what it is for you.

The compromise: paper to narrow from twelve to three. Skin from three to one.

One arm. One perfume.

Your nose can comfortably evaluate one perfume at a time. Two on different wrists is already too many — the second one will keep contaminating your impression of the first. Three is dishonest. Four is a waste of skin.

Wear one perfume for a full day. The next day, wear another. The day after that, wear the third. Then decide. The week is your evaluation surface, not the afternoon.

Smell coffee beans, then keep going.

Counters keep a jar of coffee beans for "resetting" your nose. They don't reset your nose. They give you a brief mental break. The actual mechanism is just time — your olfactory receptors adapt and unadapt on their own, and the most reliable way to recover sensitivity is to walk away from perfume entirely for ten minutes.

If you've sniffed five things in twenty minutes, you cannot sniff a sixth one usefully. The receptors are saturated. Go outside, eat something, come back tomorrow.

Pay attention to the dry-down. That's the perfume.

The first hour is mostly volatile materials evaporating. The next several hours are what the composition actually is. If you're going to spend money on a bottle, the version of that perfume you should be evaluating is the one your skin smells like at hour three, not the one your wrist smells like at minute three.

A useful exercise: spray a sample at 10 a.m. and don't smell it again until lunchtime. The difference between what you remember from the store and what you find on your wrist at noon is the actual perfume. That's what you're buying.

Don't compliment-shop.

The single most common reason people end up with a wardrobe of perfumes they don't really like is that someone else liked them. "I wore it on a date and got compliments." "My coworker said it smelled great."

Other people's noses are not a map of what's good for you. A perfume that gets you compliments is a perfume that smells familiar to other people — usually because it's recent, popular, and resembles things they've smelled before. There is no bigger sin in this hobby than buying the inoffensive option because it earned a thumbs-up from the front desk.

Wear what you'd wear if no one ever said anything about it. The compliments take care of themselves over time.