I've always taken a "Chinese first" approach with my work, and the same goes for social media. Truth be told, my audience is just not on sites like Facebook and Twitter. Weibo is still my primary venue, although I'm not as active as I once was. Here's where you might find me:
I was very active on Weibo from around 2010 to 2012 accumulating over 3 million followers, but backed off considerably in subsequent years. Still, this is the best place to broadcast messages to the public, so I check in and post stuff from time to time.
WeChat is the king of Chinese social media, but it's more of a closed platform than Weibo. I maintain a page here simply for reference. Scan the QR code or search for 大山侃大山 in the WeChat app.
I thought social media was supposed to bring the world closer together, but nowhere is the Balkanization of the Internet more apparent than in the separation between Chinese and Western social media platforms. I maintain a basic presence on these sites, but they really are almost entirely irrelevant for the work I'm trying to do, because only a small minority of my Chinese audience is here at all.
Not much of a following here, but this is the one site I think is worth developing a bit more. Mostly just posting English versions of what I put on Weibo.
I don't use Facebook on a personal basis myself, and just maintain a simple page here for anyone who is looking. Content is primarily forwarded from Instagram.
Twitter is a good place to follow journalists and China-watchers and keep on top of the most depressing news of the day. My Instagram forwards here too, but I rarely post anything else.
As with Facebook, I maintain a page here for anyone who is looking but am not active on the platform.