I just came out to my wife a couple weeks ago (talk about a difficult talk), so I'll share with you what I learned, but everyone is different so take it with a grain of salt.
* Try not to worry about what will happen. For me it was a relief to get it out.
* I think it helps to act calm and confident even if that's the opposite of what you're feeling. Don't show give them an excuse to try to 'talk you out of it'. Remember that it's not a group decision.
* Don't hedge or hold back. If you're coming out, don't stop halfway or try to break it to them easy. Just be completely open and honest and answer their questions as well as you can.
As for emotions, I can't imagine anyone not getting emotional. In my case, there was no yelling. There was anger on her part, and accusations, but I stayed calm and leveled with her and she stayed calm too. She was upset but she kept her cool and now we're trying to work it out and she's doing her best to be supportive.
I have no idea how your sisters will react, but if things get too emotional it can help for everyone to take a few deep breaths. Not sure if this helps, but I hope so. I'm no expert, just someone who recently went through something similar. Good luck!
