I'm a sophomore in high school and I came out to a few friends last year, but now that I am more comfortable with myself and my sexuality I more people to know. I'm really good friends with someone new this year, but I don't know how to bring up to subject without making it a big deal. I've also been thinking about telling my older sister, who is a senior, that I'm gay, but I don't want my parents finding out yet. I feel that I could be endangering her mental health by having her lie to my parents, though, so I am reluctant to do this. Any advice on how to ease out of the closet at a small school?
Is there a particular reason why your sister's mental health would be endangered? Is her mental state fragile? If not does she usually have issues with being able to keep a secret from your parents? Since we don't know what kind of relationship you have with her, do you think she will be supportive? As for your good friend, since you already came out to some friends, what's different about him that makes it more difficult?
When it comes to new relationships think of your sexuality in the same way you would having a peanut allergy or being a vegetarian. You don't have to announce it the first time you meet and you don't have to start up a special conversation just to make it relevant. If however, someone offers you a nut bar or a ham sandwich, you can just set them right. In other words, if somebody makes an assumptive question i.e. "what's your boyfriends name?" you can just politely correct them, "she's called Lucy" or "I don't have one but that's OK I'm attracted to women" etc. The first time you let the opportunity slip to correct someone's assumption only makes it harder to finally tell them. Keep that in mind and it should hopefully feel easier to do.
Live life the way you want to experience it, ignoring all the while the inevitable contradictions. For this above all else will others respect you. Be comfortable being yourself around everyone, not just with people you know. To your friends - and you should count everyone as your friend - you have the obligation to expose your true self and from them in return, the right to be respected for who you are.