You have educated yourself and understand the pro-LGBT stance. Although you may not agree with it, you want to behave in a caring and sensitive manner and be a role model to your students. Tolerance means you act civilly and accept another's right to be who they are, not that you like another's behavior. Here are some suggestions on how to do it.
If you want to act tolerantly, DO the following:
1. Use individual's preferred terms, names, and pronouns
2. Take each person at face value without connection to sexuality or gender identity
3. Familiarize yourself with the vocabulary and avoid slang or loaded terms National Lesbian and Gay Journalist Association’s
Stylebook Supplement to LGBT Terminology
4. Respect people's privacy. Many LGBTQ people are not "out" in all situations so please don't tell others without their permission
5. Admit to discomfort on LGBTQ subjects in a calm, disinterested manner: "I feel uncomfortable discussing this subject. Could we talk about this later?"
6. Talk to LGBTQ people about commonalities, such as hobbies or work
7. Be aware of heterosexual privilege and its affects. For example, how do same sex parents feel when a school only acknowledges/communicates with one of the parents?
8. Teach your students and own children (or future children, nieces, and nephews) to treat everyone with respect regardless of differences and disagreements
9. Learn more about aspects of LGBTQ life that you do respect
10. Remember some people will view your rejecting their sexual orientation or gender identity as rejecting them personally and will respond to you emotionally
11. Assume that LGBTQ people are in all settings, including people who are married or have children, and help create safe environments for them
12. Talk to a counselor if your feelings interfere with your relationship with an individual
13. For elementary school teachers, remind parents at the beginning of the school year that being excluded from birthday parties can be hurtful and to encourage their children not to discuss their parties in school
14. Avoid laughing along with anti-gay, homophobic, transphobic, or heterosexist remarks, jokes or comments. As a teacher, it is your job to speak up against it immediately. If you are not assertive or confrontational by nature, practice phrases to use in order to become comfortable speaking up
15. Postpone discussing issues that will likely get you heated or emotionally upset. Rationale thoughtful dialogue is difficult with heightened emotions
16. Avoid well-meaning statements that are actually demeaning such as “I still think you are a good person” or (to a transman) "you look like a 'real' man."
17. Avoid asking invasive personal questions that you would not ask a heterosexual or a cisgender person (someone whose biological sex matches their gender):
To a transgender person:
Are you “really” a man or a woman?
Have you had the surgery? or Are you going "all the way?”
Are you gay or straight?
What is your "real" name?
To a lesbian, gay, or bisexual person:
Which one of you is the "man/woman" during sex?
Have you tried sex with the opposite sex?
Are you attracted to so-and-so?
Why did you choose to be gay?
What do you think think made you gay?
~Kathy Staley, 2012, edited 2013