The key for me is just to be proactive with meeting people and making friends. If you go out (irl or online) and just be nice to people, you'll make friends, and you may end up dating some of those friends, or they may introduce you to other people you can date. Just don't worry too much about it, flirt with the people you like, and ask someone out if they flirt back. Even if you don't find anyone right away, you'll still end up with a wider social circle and maybe a few good friends.
I have social anxiety, btw, and I have a hard time talking to people I've just met, so if that works for me it should work for just about anybody. I basically just have to force myself out of the house so I can meet people.
Online dating, imo, can potentially work, but it's mostly hit-or-miss with most potential partners falling on the "miss" side. Online stuff probably works better for casual hookups with no strings attached, but it's not for me.
You're better off living in the UK, I think. The US in general is pretty transphobic, though it depends on where you live. More liberal states and cities are better for making friends and dating, and I assume it'd be the same over there.