UPDATE (June 1, 2015): Caitlyn Jenner, formerly Bruce Jenner, will be on the cover of  Vanity Fair, marking her first public appearance, the magazine announced today. “Bruce always had to tell a lie. He was always living that lie. Every day he always had a secret from morning to night,” Jenner says in a video teaser about the photo shoot. “Caitlyn doesn’t have any secrets. Soon as the Vanity Fair cover comes out, I’m free."

UPDATE (April 27, 2015): In an interview on Friday, Bruce Jenner revealed to Diane Sawyer that he's transitioning from male to female.

Being transgender isn't as unheard of as it once was. In fact, thanks to critically-acclaimed shows like Orange is the New Black and Transparent featuring prominent trans characters, as well as real people like Inside Edition reporter Zoey Tur and author Janet Mock, the visibility of trans people is higher than it's ever been. It's a great thing for a group of people who have been marginalized and misunderstood for far too long.

But now, with the frenzy of reports saying former Olympian and reality TV star Bruce Jenner is "transitioning to life as a woman" after months of (at times grotesque) tabloid buzz about his changing appearance, it seems like a good time to talk about...well, the best way to talk about this topic.

As a public figure, Jenner is unfortunately under a lot more scrutiny than the average person. But it's important to know that the decision to live openly as transgender can be difficult for many reasons, explains Jay Brown, director of program strategies for the Human Rights Campaign Foundation, and a transgender man himself.

If you suspect that a friend, family member, or colleague is transgender, wait for him or her bring it up, Brown says. "Speculation and rumors are never good. If they haven't talked to you about it or it's not out in the open, it's probably because they're not ready."

And even if someone's trans status is obvious, that doesn't mean every detail of his or her anatomy, sex life, or emotional health is—or should be—your business.

Here are five things you shouldn't say to someone who's trans or transitioning, plus how to be there for them without crossing the line.

When did you decide to become a man/woman?

Transgender people don't wake up one morning and decide they'd like to be a man or a woman; it's most likely something they've felt for a long time, Brown says. Instead, you might ask a person at what age he or she decided to come out as transgender, or when he or she began to transition publicly.

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Have you had the operation yet?

Not all people who transition have surgery, Brown says. Some take hormonal medications to trigger bodily changes (such as growing breasts or body hair), while others express themselves (and the gender they identify with) through their clothing and mannerisms alone. Unless the information is volunteered to you, it's rude to ask what's going on with their private parts. (Just as it'd be rude to ask anyone else the same questions.)

You'll always be my brother/sister/son/daughter/friend

You may think this is a sweet and supportive message, but since it's gendered it can be very hurtful. "It means they're not seeing you for who you really are," says Brown. "It's not that transgender people don't understand it will take time to adapt, but rejecting who they are right from the beginning can really put up a wall." Instead, use gender neutral descriptors—"You'll always be my sibling"—or just stick with a simple, "I love you no matter what."

It will take some adjusting on your part, and that can be challenging, especially for family members of trans people, according to the American Psychological Association. But speaking with a professional or joining a support group can help you process your emotions.

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Aren't you worried about your safety?

Violence against transgender people is a very real issue, and one that everyone should be aware of. "But when a friend is opening up to you with such a sensitive disclosure, it's the last thing you want to bring up at that moment," says Brown. "Clearly that person is worried about a lot of things—rejection, for one—so it's really best to focus on what's hopeful and what you appreciate about them coming out."

Nothing

Sometimes dancing around a topic is worse than saying the wrong thing, so don't be afraid to voice your support for someone who's come out as transgender. "People think they're being respectful by being silent, but that's not always the case," Brown says. "This person shared something big, and avoiding the topic makes it look like you're uncomfortable with it."

Instead, he says, let that person know you'll support him or her however you can. "If you're curious, ask if there are any materials they'd like you to read, or just let them know you're happy to listen if they want to talk," he says. "Even saying something like 'I love that show Transparent,' can help. It seems like a stretch, but it gives you something to connect over, and shows that you're supportive."

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