There is this thread
http://www.hypermobility.org/forum/viewtopic.php?t=2756 on telling people at school, but I dunno if it quite what you are looking for.
I too am almost unable to sit and explain HMS/EDS to people without crying. I have a number of strategies (apologies for the length):
1. for people who are casual acquaintances: An overly simple "I have EDS it means that my bones aren't held in place properly, and yes, it does hurt."
2. For people I see a lot (like work colleagues) (Note, I got on very well with colleagues at work, which helped a lot). I found that people just couldn't take it all on board at once. So I told them a little at a time. Over a few months I built up their knowledge. I was using crutches at work cos of pelvis pain before diagnosis, so they knew I had problems with that portion of my anatomy. After diagnosis I told them "I have EDS it means that my bones aren't held in place properly, and yes, it does hurt." Then later "could you help me with x - my wrist just subluxed" and later when someone commented I looked tired ‚ "yes, it's part of EDS - my muscles have to work overtime to keep me together, plus I have trouble sleeping because of pain, so my normal is probably your feeling like you have flu." etc. It was difficult, but it meant that I only had to say one sentence at a time I was less likely to cry. I also gave my manager a written blurb on how it affected me.
I would also often explain something the next day, for example when in lots of pain I can be really short with people, like I am really offended. At the time there is no way I could explain why without melting in tears, so the next good day I said "sorry for being so ratty the last few days, x was hurting so much I felt sick - please don't take it personally if I sound cross with you - the chances are it is because I am in pain."
I also got the first aid guy to agree to a "first aid for hannah" procedure - basically don't touch me unless I give you permission, or I am unconscious and it is essential, don't call an ambulance unless I agree - dislocations are normal, and don't EVER put me in the normal recovery position (pelvis would never forgive them

) I also did an info sheet to hand to paramedics if needed. That meant I knew that if anything happened at work I wouldn't need to worry or try and explain. (I did this after I collapsed at work one day and was struggling to explain stuff to the medics - then I collapsed again and my manager just handed over the sheets and hey presto, they were fully updated on my condition

)
Another option is to write a letter about it. There is a sample letter on the homepage which is really good. I adapted this and showed it to some people I am close to. I also did one for my boss at work.
3. Writing it down in letter or email form. last week I sent an email to my old uni friends to let them know as in my profession everyone knows everyone so they would otherwise of found out on the grapevine. - a very basic info note, very hard to write, but enough to stop them being horrified if I meet them unexpectedly and I'm in a wheelchair.
4. with friends I also used the little by little approach. And decided to give them useful pointers at times when they weren't imminently relevant, so they had time to sink in and also I wouldn't cry when explaining. like when I was round a friends for coffee I mentioned that I really appreciated being asked to do stuff with them cos then if it is a good day I can say yes, but if a bad day, I may say no but I am reminded I am still one of the gang. I would far rather be invited and say no than be left out.
It does take a lot of courage, and you will probably have to cope with the 'I'm sure theres a cure' or 'but it doesn't affect you that much' comments, but usually these are because people are struggling to come to terms with what you have told them. For me though it had definitely been worth the effort - you can't expect to get the support you need if you don't let people know just how bad things can be.
I'm not sure how much sense this is making, and I think it may be wise for me to shut up now

If you want more info/clarification on anything I've said (or not said) feel free to ask either here or by pm.
Hannah