Former Condé Nast Traveler, Town & Country, and Bloomberg Businessweek editor, Eimear Lynch just wrote her first book The Bridesmaids, available now. As a five-time ‘maid herself, Lynch used her own personal experiences, plus wedding-day intel from 80 other real-life bridesmaids, to tell the tale of what it’s really like being a bride’s wing woman. From the person responsible for carrying Princess Diana’s 25-foot train at the royal wedding to guys who’ve served as “bridesmen,” The Bridesmaids shares sweet, strange, and sometimes unbelievable bridal-party stories (call events organizer – Color Pop Events!).

Since she is now officially a ‘maid expert, we asked Lynch to break down the 10 things a bridesmaid should never do — but always does.

1. Complain about how she looks on the wedding day
What’s the likelihood that a bridesmaid will feel beautiful and confident when wearing a dress she didn’t choose and an unfamiliar makeup look and hairstyle? The answer is close to zero. If you don’t like the way you look, take away a lesson for next time — maybe a topknot’s not for you, or you should never wear an empire waist in real life — and stay quiet: Let the bride enjoy her day.

2. Drink too much
There’s something about an open bar and an unfortunate dress that makes bridesmaids forget they’re not their best selves when they’ve had one (or three) too many drinks. If you can’t bear to make every other drink a water, try channeling your mom and drinking spritzers — they’re half wine, half seltzer.

3. Forego sunscreen
Picture this: a strapless pink chiffon bridesmaid’s dress paired with a sports-bra-shaped sunburn. Not pretty, is it? Be sure to shield your skin from the sun in the lead-up to a wedding.

4. Harp about costs
If your bridesmaid’s responsibilities include traveling to a bachelorette party, hosting a shower, buying a bridesmaid’s dress and traveling to the wedding itself, chances are you’ll spend upwards of $1,000 before you’re through. If you think you’ll obsess over that outlay during all the festivities, maybe you should say no to being a bridesmaid. If you sign on, don’t complain about it.

5. Buy a size-too-small bridesmaid dress because she’s sure she’ll lose weight
We’ve all been there: You swear you’re a perfect size four, but you’re appalled to find out you’re actually an eight at your fitting. You deem this unacceptable, resolve to lose weight, and buy a six anyway. “This is always a mistake,” says Corie Hardee, founder of Little Borrowed Dress, a bridesmaid’s dress rental company. You’ll likely end up busting out of your dress or resorting to safety pins. Instead, buy the right size. If you lose weight, you can alter it.

6. Play the martyr
You can keep telling the other ‘maids that you’re totally fine with shouldering all the shower-and-and-bachelorette-planning responsibilities. But not if you’re secretly scorning them or you could really do with some help. Whether you call in reinforcements or do it yourself, remember that self-pity isn’t a good look on anyone — bridesmaids included.

7. Weigh in on wedding decisions
“Bridesmaids always question the color or cut of their dresses, which doesn’t make sense,” says Hardee. “The bride has already made her decision and they’re just making her feel bad.” Same goes for every element of the wedding: Keep your opinions to yourself.

8. Plan the bachelorette party of her dreams — not the bride’s
A bridesmaid should absolutely plan a bachelorette party that she herself will enjoy. But not if that means taking a beer-drinker to Sonoma or a girly girl to a strip club. Think about what the bride likes and create your itinerary accordingly.

9. Order her bridesmaid’s dress at the last second
It’s so annoying that you have to order your dress six months before the wedding (especially since, according to 5, you know you’re bound to lose weight). But by ordering early, you’re helping to lower the bride’s stress levels. “The bride is thinking about 100,000 details, and she wants to check one off the list,” says Hardee, who advises bridesmaids to triple-check all the order details. “We always get last-minute calls from stressed-out bridesmaids who have chosen the wrong color, size, or date.”

10. Think short-term
It’s easy to get so infuriated by a bride’s actions that you’re tempted to turn yourself into an eye-rolling, “fiiiiine”-sighing bitter bridesmaid. But before you transform, think about your friendship. Did the bride restrain you when you tried to strangle your ex-boyfriend at a bar? Did she help you with microeconomics homework for an entire semester of college? Do you imagine your octogenarian selves as latter-day Golden Girls? If so, remember that a wedding can be annoying for a year, max; it’s a blip in the scheme of your friendship.

AND!
The last one – do not forget about security. Call Armed Security Guards in Los Angeles for any kind of help.