From Goodreads:

Chapter One: Telling Yourself; Telling Others

The first person you have to come out to is yourself. Anyone who has been through this process can tell you that, depending on your circumstances, this can be either the easiest or the hardest part of the whole process. If you are lucky, you come of age in a liberal, tolerant atmosphere, attending a school with other smart, sophisticated young people for whom being thought of as prejudiced is a worse taboo than any difference you could present; perhaps you've had an openly gay teacher, or your parents have openly gay relatives or friends whom you have come to know. In such a case, acknowledging your sexuality is a path that has been smoothed for you.

If you are not lucky, you live in a conservative community where boys still use the word "faggot" as a taunt, you had a gay teacher who everybody knows about but who would sooner die than present his sexuality publicly, or you have parents who profess religious beliefs that are dependent on scapegoats for a sense of personal righteousness (and that set of scapegoats nearly always includes homosexuals). In this case, accepting your own sexuality will be harder, as you will know damn well that being known as gay in such an environment could lead to grief, if not bodily harm or ostracism from your family.

Your first step in either case is going to be to look in the mirror and say to yourself, "I'm gay." No, you don't have to make your first announcement over a public address system like Ellen DeGeneres's character did on the show. Maybe the first time you say it you have to whisper it to yourself in the bathroom, with the door shut, the water running, and the fan on. But whatever the age atwhich you come out, this has to be the first step. For some gay men it's a knowledge they're born with; for others it's something they repress and deny for years.

No book can tell you how to accept the fact that you are gay. What a book can do is help you after you've accepted that fact, even if that acceptance comes laden with feelings of guilt, shame, and fear. The process of coming out is the process of dealing with those feelings, both in yourself and those around you, and building your self-esteem by standing by