How does who do what? If you mean manipulate the share price,...

How does who do what? If you mean manipulate the share price, take a look at the course of sales for today. I wouldn't be surprised if 25% of the trades were for less than 10 shares. Clearly these are not retail investors, so can only be bots (whose controllers do not pay minimum $10 trade commission like most of us), and their only purpose can be to influence the share price.

Also take a look at shortman, and you will see the proportion of a given day's trading volume that is short-held stocks. The last two reported days (27th and 28th November) were 52% and 45% respectively.