Look at strengths that you want to "display" (i.e. leadership, community involvment, initiative, ability to adapt to unfamiliar terriroty, etc)...then look at all the antecdotes in your life, and pick the situations that best demonstrate said attributes. That's your story.
Just my 2 cents, and perhaps I'll get flamed for saying this, but I would hesitate to mentioned sexual orientation as part of your story. I don't see how one's sexual orientation is a basis for one falling under the diversity tree, and trying to spin it as such may really back-fire. I would only mention it if you participated in a reputable community organization for LGBT and your involvement illustrates key leadership attributes.
But then again, you may not want to listen to me - I am after all reappying this year