Every situation is different especially when you decided to come out and reveal your position with relatives such as parents, siblings or friends that you're close to. Yet what I am about to layout are for adults and not children.
It's important to start with thinking about the purpose of your communication, and that is just to come out to them, that is to come out of hiding and let them know who you are and what you've been struggling with. The goal is to remain as close as possible to your family and be accepted and hopefully supported by them in the future. Remember you are the only one who knows very well your own family, especially their beliefs when it comes to the LGBT community or issues they might have seen on the media regarding the LGBT community.
You must also consider if you should come out at all. If you are still dependent on your parents/family (under 18, or if they are paying for college, etc... ) then you need to think of the possibility of their cutting you out or off. The last thing you want to be is a homeless transgendered youth. If this is the case, then it may be wiser to spend some time finding and getting support before proceeding.
If you decide that the time is right and it's safe to come out to them then...
How to approach it:
My experience has been with Transgendered clients, that a letter works best. The letter has several advantages over face to face communications.
You get to take your time and think about what to say and word it perfectly.
You can have a friend; therapist or supportive person read it over first and give you feedback.
You can't be interrupted in your communication.
Your family member can go back and read it again and take their time with it.
Why a letter and not an email? Well, a letter is more personal, email can be a little cold.
What to reveal:
I'm of the school of thought that you should just say it in your own words as clearly and plainly as possible. I think it can be good to also include the following:
Reassurance that you love them and want to remain connected and hope that they will be supportive.
Reassurance that this is not their "fault".
A little bit about your struggle with gender over the years, your experience, coping, isolation, etc... (be specific! It will help them empathize with you)
A few recommendations of books, articles or support groups in their area
and I recommend to ask them specifically not to respond right away, but to take some time (a week) before they respond. Let them sit with it and what they just absorb. This will prevent any immediate bad or negative response and let them calm down.
Just as you would tailor a cover letter for a job you may need to tailor your coming out' letter for different family members. Your parents are two (or maybe more than two) separate people, invite them to respond individually.
What not to communicate:
There is no need to talk about specific long term plans/timetables or surgeries in your coming-out letter. Remember, the purpose of the letter is to let your family know that you are transgendered. Period. Future plans are better left for future communications. Why? Because just digesting the fact that one has a trans son/daughter/brother/sister is enough to begin with. I think it's OK to gently allude to the fact that changes might be coming in the future, but I wouldn't go farther than that in your first communication on this topic.
There is no need to go into the origins of transgender or even throw at them topics that would only allow more confusion. There are too many conflicting theories biological and otherwise, and even if you knew the origin of your being transgendered, it wouldn't change it. Try not to justify your position just yet.
The Results or Aftermath:
If you get a positive response that's great! Otherwise stay calm, even if you get a negative first response. Give them time. Remember, you've had a lot of time to think about this and are ready to move ahead. They are just learning of this for the first time and need to absorb it.
Don't be reactive to a negative response. Be the adult (or if you don't feel it, just pretend). Remember the long term goal is to have them be connected to you, maintain a good relationship with them and have them be supportive. Keep the long term goal in mind in all your communications with them.
It does happen sometimes that parents have a very negative response and even reject you outright. This can be very hurtful and disappointing. When this happens, again, don't be reactive no matter how you feel. Keep the long term goal in mind. It's easy to "write them off", but ultimately unsatisfying if you want to have your family.
How to handle a negative response:
Communicate that you are open and ready to talk when they are,
Be understanding with their difficulty in accepting/understanding/assimilating this information. Understand that they need time and may have a religious/cultural basis of understanding that can't be overcome quickly.
Express your wish and hope that it will change over time.
Ask what you can do to help them accept this?
For those of you who are contemplating about coming out to your family and friends, but are not certain how to approach it, due to you knowing your family very well. Feel free to contact me here at Transgender Insight and I would offer my support and advice.