Lesbians, gay men, bisexual and transgender people are everywhere, and it takes a lot of courage to be true to yourself, especially when some people might disapprove. It takes a lot of good character to cope with life sometimes, and people in the LGBT community tend to show these excellent qualities from their life. If you are respectful and open-minded, you could make some awesome friends who might help you learn to be braver and truer to yourself too!

[edit] Steps

Understand Gay and Lesbian People. Learn that gay men and lesbians are no different from any other group of people:
- Forget about stereotypes - gay men and lesbians lead a huge variety of lifestyles; not everyone is obvious in their appearance or their actions.
- Accept the fact that the ability to love or care for another is not solely related to sexuality, and that all relationships, whether heterosexual or homosexual, are built on mutual attraction, love, respect and trust.
- Understand that gay and lesbian people do not choose to be gay and cannot make themselves straight; just as straight people do not choose to feel attracted towards the opposite sex.
Be open minded, as you would be with any other person. There are nice and mean gay people; just as there are nice and mean straight people. It takes a lot of good character to cope with life sometimes, and people in the LGBT community tend to show these excellent qualities from their life.
Do not assume that a person is sexually attracted to you. If you are female, do you assume that all straight boys are attracted to you? If you are male, do you think all straight girls are interested in you, just because they like boys? That would be ridiculous! The same thing applies to everyone; just because a person is attracted to your gender does not mean that they are sexually interested in you.
Be respectful. If you have questions, be aware that you may be treading on sensitive ground. Would you appreciate being asked about your sex life by a work colleague? Probably not. A gay or bisexual person may wish to disclose their sexual preferences with you, or they may not. Don't assume that you can change someone, and offering to do so is offensive, and impossible. Could someone of your gender change your orientation?
Be aware that it took a lot of courage for someone to tell you that he or she is lesbian, gay, bisexual or transgender, and that it is a gift of honesty and trust. It is important to that person's integrity to be honest about themselves, and you owe it to them and to yourself to be as understanding to them as you would want them to be with you.
Realize that friendship with a person who is lesbian, gay, bisexual or transgender is no different. If you have friendships with member of the opposite sex, its no different to having a friendship with someone who has a different sexual orientation than you. Be yourself - people will be able to see through attempts you make to hide what you're really thinking and feeling.

[edit] Tips

Do not be afraid to talk to anyone. You may not even know that someone is LGBT or straight; it doesn't make any difference to how you should act.
Remember that homosexuality is an orientation, not a preference.

[edit] Warnings

Just as it would be inappropriate for a gay or lesbian person to impose his or her view upon you, be careful that the expression of your view, whether religious or not, does not make a homosexual feel that they are evil or untouchable. If you truly want to understand them as people, you will need to approach the subject with an open mind. Disapproving of the sin should not make you hate the person who you believe to be sinning.
Hostility will most often be met with hostility. Simply try to open a dialogue rather than lecturing based on your past knowledge or experience. Opening yourself to a person and truly making yourself willing to hear him or her can go a long way towards real understanding between both of you. Using derogatory slang is - at the very least - thoughtlessly using language that shows to other people that you don't respect the LGBT community.