(CNN) -- My book, "Save the Date: The Occasional Mortifications of a Serial Wedding Guest," chronicles my life through the many weddings I've attended, from the nuptials of distant relatives I witnessed at the age of 8 while wearing a ruffled lavender dress, to a far more recent event at which I wore red silk and suede pumps and accompanied a new boyfriend.
More important than my age and attire, though, are the experiences I've had and what they've taught me about love, friendship, myself, and (not least) being a wedding guest. Here's what I've learned.
1. Weddings are not just about the couple getting married.
Make no mistake, the lovely twosome about to wed are who you're there for; this event is the reason you took three days off work and put $800 on your credit card. But no modern wedding would be complete without a group of friends and family there to support, cheer on, and sometimes roast the happy couple.
In the wedding ecosystem, what keeps everyone grooving out on the dance floor, clinking glasses with forks and weeping happy tears are the strong interrelationships between the people there. A wedding wouldn't be a wedding without the guests.
2. You can say no to a wedding without saying no to a friendship.
I wish someone would have told me this early on in my wedding-going life, I might have saved a bit of cash. There are times when it simply doesn't make sense to go to a wedding, for your own personal reasons: finances, lack of vacation days, familial obligations, state of mind. But this doesn't necessarily mean the end.
A few years ago, some very good friends decided to marry in India. I'd just started a new job and couldn't afford the time off or the cost of the trip. So I said no, and, months later, got to attend their legally binding U.S. ceremony at City Hall in Manhattan. As my dad told me when I interviewed him for "Save the Date": "It's the journey, not the destination." That's what matters in a friendship, too. It's not the one day, it's all the days.
3. Give the gift you want to give.
This is a controversial statement, but I'm standing by it — with some caveats. If you know the marrying couple well and the gifts on the registry seem impersonal and you have an idea for a present you know they'll love, by all means, do it.
"It's the thought that counts" should apply to everyone in receipt of a gift, including people getting married. You can also include a gift receipt, just in case.
4. No date is better than any date.
It can seem tempting (particularly in later years when people are beginning to pair up) to grab the nearest available sir or madam and ask them to attend the wedding with you. Consider that move carefully. Just because someone is able to put on a suit and tie and sit at a table does not mean you want him there for what's bound to be an emotional moment in a dear friend's life (and possibly yours, too).
It's really freeing to go to a wedding by yourself, to know you can do it, and not have to take care of a date who may not know anyone else there. It's even better not to go to a wedding with a person you hardly know, who ends up behaving poorly.
5. Open bars are not your enemy, but open tequila-shot bars might be.
Enjoy the signature cocktails and the refills of good white wine, but be careful. Know your limitations, even as they seem to grow farther away the more you drink.
Drink water between every glass of something stronger, or just make sure to drink water. And if there's a tequila bar set on the cliffs at a destination wedding in Jamaica, limit yourself to one shot, lest things get too murky.
One of the most obvious things a person should do is eat the food provided. After all, the couple has gone to the trouble of choosing it. But weddings can be full of so many things to see and people to talk to and all of a sudden they're playing "All the Single Ladies" and you just want to get up and dance and where's that cute guy again, the one who was making goo-goo eyes at you from table 13?
Only later, you may realize that you don't feel so well, what with the signature cocktails and the fact that all you ingested was a couple bites of the salad they served before the main course. And you end up back in the hotel room, eating Cheetos or a granola bar or an old, bruised apple from the bottom of your duffel bag, making goo-goo eyes at no one but yourself. So eat.
7. Don't flirt with the staff.
This can seem tempting. They are so nice! They are serving you, giving you whatever you need, before you even know you need it! Note: They are paid to do this. This does not mean they want to be your friend, nor your new boy- or girlfriend. They are doing a job. So treat them professionally and kindly, and go flirt with someone else.
8. Do flirt with other (single!) people.
This is part of the fun of a wedding! But make sure they are single, because sometimes, even at weddings, people don't tell you this right off the bat (trust me, I know). Also make sure that they are not a relative of the bride or groom or a person with whom it would be very awkward or potentially disastrous for you to flirt ... the bride's dad, for instance.
If the bride or groom has highly recommended a particular person to you as a hook-up, you are free to go for that person or ignore him or her completely in favor of another. You don't have to do everything they say, just because it's their wedding day.
9. Your feelings are legitimate, whatever they may be.
Depending on where you are in your life, you may not be attending the event with the most positive, rose-colored-glasses vibe. You might feel downright crappy about love, relationships or what you see as a lack of success. If you feel that way, acknowledge it and hang out with it for however long you need. Go to yoga, get a massage, buy a great new dress, go on a 5-mile run, watch a "Law & Order" marathon, or whatever it is that you do to treat yourself before you go to this event.
But once you're there, try your best to be in the moment. You may find that when it's all over, you'll go home feeling a lot better. And if you don't, you can wake up the next day and try again.
10. Honesty really is the best policy — including to yourself.
Above all, be real. Let yourself feel what you feel. If you have something to tell the bride or groom before they get married, do it, with kindness and honesty. But do it weeks or months before the ceremony or reception — not minutes!
Also be honest about what this day means, how you would like to celebrate the people you are there for and how you would like to celebrate it for yourself. If you mess up, to yourself, to anyone, apologize.
11. There is no such thing as a perfect day.
Something will go wrong; these meticulously arranged parties with numerous guests are chock-full of opportunities for just about anything to go a little bit awry. But the only thing that can really go wrong is letting whatever goes wrong ruin the day — and this goes for the marrying couple as well as the guests.
Take what happens in stride. This is only one day; the couple have the rest of their life together, and you have the rest of your friendship life with them, too. Plus, often the things that happen that no one planned for are the things that make a wedding most memorable, and the things you'll all still be laughing about 20 years from now.
Learn more about the author at jendoll.com.