Where to write a diary in Chinese? Practicing Chinese is hard when you are not following regular lectures or if you do not know anyone with who talk.

Beyond practicing everyday following a book or an app, I would like to write regularly something on my own, like a mini-blog or a Tweeter. This would keep motivation flowing from the fact that other people can read you, and learning from the words and syntax rules you need to check each time.

However, is there a typical place where to do so, where competent people can read and correct you?
If you are interested in writing AND having native speakers correct what you write, then you should definitely try out lang-8.com. The website allows you to do exactly that. 

Technically it's not a (micro-)blogging platform, but if your goal is to improve your Chinese, that might be a reasonable compromise. And nobody will stop you from writing diary-like posts if you like.