Come out when you're calm
If you come out when you're upset or fighting, the perception may be that you're just saying something to be hurtful. Stay calm and act like this is just another piece of news so that your family may not have a big reaction.
Have a fall-back plan
There can be some hard times between initial sharing and settling down. If you still live with your parents, it's a good idea to know where you can go if they're very upset or angry and you need some time away to allow them to calm down. It is also a good idea to set aside a little bit of money.
Break the news gently
One way to slowly break the topic and gauge their eventual reaction, is to start introducing conversation about it into the home. For example, mention a policy or law that could affect LGBTQ+ people. This might give your family some idea of what's on your mind and make your disclosure less surprising.
Know their first reaction is not forever
Many parents react to the idea with shock or surprise. Even if they are accepting, they might not have considered that this would be something that would personally affect them. They may ask a lot of questions, some of which seem ignorant to you. It's best to stay calm and prepare responses to the typical questions. For example, you might reinforce that sexual orientation and gender identity are not choices, but ingrained and biological.
Remember that coming out is a lifelong process
At some point in our society, we may stop making assumptions about someone's sexual orientation and gender identity. Until then, remember that you will probably come out over and over again to new employers, friends, and loved ones.
Remember that if you feel unsafe, it's okay to not come out. No one ever has the right to come out for you, and no one should ever share that information without your permission.