pip3 on ubuntu 16.04 LTS for a user

When performing

sudo pip3 install --user -U youtube-dl 

I get 2 warnings:

1. WARNING: The directory ‘/home/mue/.cache/pip’ or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo’s -H flag.

2. WARNING: The script youtube-dl is installed in ‘/home/mue/.local/bin’ which is not on PATH. Consider adding this directory to PATH or, if you prefer to suppress this warning, use –no-warn-script-location.

Questions:

Concering 1. How can I resolve this?

Concering 2. Do you recommend ideed adding this to path. If yes: What is the command?