10 top etiquette tips for the social-media age

How do you defriend your ex? Is it okay to ask someone out by text message? In his book 'Social Q's,' New York Times social etiquette columnist Philip Galanes offers solutions to some of the peculiar quandries of our age.

1.How outspokenly critical should I be?

One reader wrote in asking if she should have told a stranger that the woman's leggings were a little too see-through. "Not unless you're the host of one of those horrible 'fashion' reality shows and you've run out of young assistants and hopeful designers to beat up on," Galanes replied.

Should I intervene on public transportation?

Other passengers don't offer those in need seats on the subway? Galanes says you have the right to speak up. "It's not a big imposition to stand for a few minutes so that less able people can sit," he writes. "And whether the young 'uns ultimately agree to give up their seats, the request will only take a few seconds." Someone treating a child unjustly in front of you, however, is a matter in which you can't intervene, says Galanes, if it's only verbal. "It's even harder to see how a stranger's intervention on a subway car will help matters – or to know, for sure, if help is even needed," he writes.

What can I do about slow cellphone walkers?

One reader vented over his annoyance with dodging fellow pedestrians who were talking or typing on their mobile devices. Galanes says this is a grin-and-bear-it kind of situation. "Hate to tell you, but typing on the street has become a basic human right," he wrote in reply. He urged the reader to just watch for the slow walkers so there weren't any sidewalk pile-ups. "Our best alternative on mean sidewalks is to keep our eyes peeled," Galanes says.

Do I pay for that ride?

In an age of environmentally friendly carpooling, Galanes says passengers should always offer money to someone they're getting a ride from. "Keep that cash flowing," he writes. "For gasoline, tolls, and parking, even the occasional Slurpee from the 7-Eleven. It doesn't take much – and sometimes the offer alone suffices – to let the drivers know how much you appreciate the ride."

How do I keep peace with my cubicle neighbor?

For the grating little habits of the person in the next cubicle, Galanes suggests putting the problem on yourself. "In the calmest voice possible, say, 'You know, I have no right to ask, but you could you stop [INSERT HIDEOUS HABIT HERE]?' " he writes. "Then add, with a big smile, 'For some reason, it's really getting under my skin!'... .You avoid defensiveness and even the prospect that there's something to be defensive about."

Can I flirt in a text message?

Keep anything serious out of a text message, says Galanes. "Just as e-mails and texts may shield us from feeling vulnerable when we broach a tricky subject, they also seem less heartfelt (and serious) to their recipients," he writes. "In short, it puts 'Will you go out with me?' on a par with 'There are doughnuts in the fortieth-floor conference room!'"

Must I friend everyone?

When in doubt, Galanes says, often it's best to accept a Facebook friend request. One reader asked about clicking accept to the friend invitations from two siblings they dislike. "Our chances of getting away with 'ignoring' friend requests indefinitely – particularly among family and people with whom we're in frequent contact – seem slim," he writes. "So keep the peace and friend the whole clan."

How do I brush off an online suitor?

If you're on an online dating website and someone reaches out to you that you're not attracted to, Galanes says to be considerate. "If someone initiates a chat with you online, or sends you a message, respond as politely as you would at a bar or a bus stop," he writes. "If this person goes so far as asking you out – even though she has the audacity to not be your cup of tea – how about a simple 'No, thanks'? Don't ignore her messages."

How can I unfriend my ex?

Galanes says to proceed with caution when considering unfriending an ex and his or her family and friends on Facebook. "Leave everything status quo for a few weeks, then begin a meticulous pyramid of defriendings," he writes. "Prune out the ex's distant relatives, then casual friends, then immediate family and posse – in that order – and leave several days between groups. Boot the ex after a period of pure silence."

What about those awful photos?

One reader wrote in to say a grandmother-in-law took delight in taking unfortunate photos of family members, then sending them to the rest of the clan. Galanes says to let it go. "I'd let the old bird have her fun," he writes. "Just commission another of your rank to take kinder pictures. The beauty shots can serve as the official record of the holidays, and Granny's photo album, the blooper reel."