I don't know if you are looking for very specific examples doglover, but the most common ways are directly, through face-to-face conversation or in writing (usually a letter or e-mail). Some people are using text messages or social media to get the message to many people at once, but that may not be the best way to tell parents or siblings. When it comes to telling work colleagues, fellow students and acquaintances, you can just mention it casually in conversation, if you wish. For example, if you are asked about dating or relationships, or weekend/holiday plans. Some people are more inventive and have done things like bake a coming out cake, but that may not work well for everyone, or in all situations. Before coming out, some people like to leave clues or drop hints. I personally started talking more about gay celebrities, news stories etc. and I "borrowed" some gay lifestyle magazines to read and leave lying around. I don't know if any of that helps. If you want something more specific, let us know.
Over text message to a friend Me: Can I tell you something important? Friend: yea sure Me: ...I'm gay. Friend: really?!?! Me: Yeah... Friend: okay. In person, best friend. Me: ___ I need to tell you something. Friend: Okay, what is it? Me: Well, I've been really annoyed with my siblings lately. Also, I'm gay. Friend: Oh that's too ba- Wait, what? Me: Yeah. Friend: Okay then. So, do you have any crushes? Coming out casually: Me: (Initiates discussion about something totally unrelated, gets to something that has to do with LGBT+ issues.) Me: ...This is coming from someone who is gay, and I think that it's completely irrelevant that... Random person: (Continues conversation and silently takes in the coming out part.)