I know this technique from long time ago and i used to show it to every designer i know and always see how they be shocked

1 - first this are the tool that the technique work with

2- Select any line or shape for example we will use (rectangle tool ) while you are holding the mouse keep your finger on the left side button and press on (Ctrl + ~ ) and keep pressing and play with mouse

3-

in this way you can get results you can archive with standard tools or you needs hours to make. i hope the tutorial is clear

and asta la vista