5.18. What should pro-democracy Chinese living in China do about the dictatorship? 想要民主住在中国大陆的人应该干什么?

First of all, hide and stay safe, unless you can deal the final blow. From World at war, 1973, ep. 16:

A dictatorship is like a snake. If you put your foot on its tail as you do it, it will just bite you and nobody will be helped. You have to strike the head.
独裁就像一条蛇。 如果你在这样做的时候把脚放在它的尾巴上,它只会咬你,没有人会得到帮助。 你必须击打头部。

Once that is taken care of, a few good options are:

  • hide your thoughts, manipulate your enemies, infiltrate the corporate, political and military power circles, and go up the ladder

  • if you are an technological innovator, leave China and come work for the West. Don’t strengthen commie power.

    Alternatively, with technology you could also try the anonymous rebellion route, but the risk of getting caught is significant, leaving the country first is likely a good idea. See also:

If you don’t manage to do either of the above, don’t do any technological work. Go work on the fields or washing dishes. Working well for Chinese companies makes the Chinese Dictatorship stronger and more deadly. See also: Embargoes make dictatorships stronger (禁运使独裁更强大).

And regardless: remind your kids that the commies are bastards every day.

Related:

Lu Xun 1930 petition
Figure 72. Petition quote by Lu Xun (鲁迅) 1926. Original quote: "请愿虽然是无论那一国度里常有的事,不至于死的事,但我们已经知道中国是例外,除非你能将’枪林弹雨’消除。" (Petitions are a common thing in any country, it is not something that results in death. But we already know that China is an exception, unless you can avoid a "barrage of bullets"."). Visible e.g. at https://www.marxists.org/chinese/reference-books/luxun/09/016.htm but also at https://www.zhihu.com/question/54231137/answer/277760001 鲁迅的文字有多一针见血? (How sharp is Lu Xun’s writing? that answerer dude has balls! A chenyu is used: https://baike.baidu.com/item/枪林弹雨/31136 枪林弹雨.