I cannot speak for all people on the spectrum. I can only speak for myself and by way of witness I can speak a little for my son.
What comes to mind...
I am human...even though some of my mannerisms may differ from yours. That does not make me less human than you.
I am human...I have feelings and emotions even though you may not see them. I feel love, pain, sorrow, anger, frustration, warmth, comfort, empathy. I can feel emotions like you can, maybe even more so.
I am human...I may not be able to respond to you in a way you would consider normal, but I can respond. You just have to get to know me and you will understand.
I am human...I have a voice whether I am able to speak like you or not. Learn my language so you can hear me.
I am human...I have difficulty answering questions right away. Be patient with me.
I am human...I have the ability to learn if you have the patience to each me. I am human...I want to be recognized for being who I am. I am so much more than a label. I am me. See me.
I am human...I am not a punishment. I am a gift. Your child. My life is precious and my love for you, infinite.