Newly diagnosed, who do I tell

The way I have come to handle it is, tell one trusted friend who knows others of your circle. they can do the rest without making it awkward. I also lead with it if it seems the person I'm talking to will be a part of my life for some time and maybe a potential friend.

This gives the person some idea of what to expect and gets the disclosure thing out of the way: no more imposter syndrome or excessive masking! Sometimes I will get the cringe-worthy "funny you don't look.." and some such comment, but often it can be "oh we thought so", or "of yes you are!", "thought so" or "that explains so much, thanks". From there we  can move on without the unsaid "something weird" hanging over us.

If people are susceptible to systematizing stereotypes, I probably wouldn't want to hang with them for long anyway.

Some become standoffish but warm back up when they slowly realize how enriching being with someone who is different can be -  or that I will NOT be reciting the periodic table to them with "fun facts" about each element - not at first, anyway. 

I also say things like  "please slow down. I'm on the spectrum." without hesitation when customer service goes too fast for me to write down what they say, for example.

The main thing is not to be apologetic, but to definitely own who you are with confidence.

I think ND people find each other. Us older folk have (me late 60s), mos def, autistic friends who would never think to consider whether or not they are on the spectrum, but they SO are. Find your tribe where you feel valued and seen.

What if you’re in a tribe of one and can’t relate to anybody?

Unless you enjoy being that way. If you don't then it is a matter for experimentation and investigation: find where and with whom you belong by experimenting. Other people are time consuming and I understand the urge to just feel at home and have friends just be there when we like, but friendships are work, enjoyable work if your inclined but there it is. IF you don't enjoy it, yea, one is the number.

Unless you enjoy being that way. If you don't then it is a matter for experimentation and investigation: find where and with whom you belong by experimenting. Other people are time consuming and I understand the urge to just feel at home and have friends just be there when we like, but friendships are work, enjoyable work if your inclined but there it is. IF you don't enjoy it, yea, one is the number.