Don't let people who are ignorant about it (or just trolling?) like
>>2 get to you.
>>3 gave good advice imo, but it might not be applicable to everyone's situation. Some people just *have* to tell everyone at once. This could have great results for some people; others might wind up homeless, friendless, etc. Feel it out for yourself and decide whether you want everyone to know, or just a few people, or just one person. Maybe you'd only want to be out at school but not at work/home, or vice versa. It's really up to you what pace you go at with this. Just make sure you about it carefully. (I always asked myself which choice I would regret most.)
Also, make sure you can recognize when someone misgenders you purely by accident. Even when people are trying, they'll still mess it up sometimes! Try to be patient with them in that case. On the other hand, you'll probably have no issue recognizing when someone's being plain malicious about it. If it's physically safe to do so then don't be afraid to correct someone. You deserve respect just like the rest of us.
Depending where you live, it might take longer for some people to understand and come around. The key thing to look for is whether they're actually trying to understand, or whether they're just trying to preach to you. Sometimes you'll talk to brick walls. Sometimes people who love you might try to "fix" you, change you, convince you that you're wrong about your identity and that they know what's best for you. In lots of cases, they still love you - they're just loving you the wrong way. Remember that. It might be what keeps an important relationship from dying completely. Sometimes winning someone's acceptance takes time, effort, and lots of honesty.
A couple other random tidbits I guess??:
> If you're FTM and need help accessing binders, I know Point of Pride lets people apply for free ones, with descrete packaging. (For MTF I'm not sure if PoP also does packing, but I'm sure you could find other organizations out there.)
> If you're underage and don't end up coming out to your parents (or they don't want you presenting as your true gender) but still want to buy things for binding/packing, wait til it's around a holiday/birthday to order one online. Tell your parents it's a gift ahead of time so they can't look inside. That might not work depending how strict they are, but it worked for my friend.
Hope any of this was helpful. Wrote this in a rush so it's probably a bit jumbled... Anyway, I'm wishing you the best, OP.