Better use of available tools

In the instructions you use the following to kill remaining Docker processes

`ps aux | grep docker | awk '{print $2}' | sudo xargs kill -9 2>/dev/null`

Of course it does the job, but imho you should use awk to its potential as in

`ps aux | awk '/docker/ {print "kill -9", $2}' | sudo -i 2>/dev/null`

Fewer processes, no xargs as `root`.