It's simple. Select the "smart ABC" input method, then press the "V" key, then press the number "1" on the numeric keypad above, and finally press the space bar to input blank characters. This blank character is different from the space entered with the space bar. QQ server can be tricked into thinking that it is a character, so that the name and signature can be blank. As for the avatar, it is also very simple. You can search online.