Install Python3 via homebrew (Optional: in case you do not have pyhton installed. run python3 --version to see if it's installed)
$ brew install python3
Install powerline via pip (python package manager)
$ pip3 install powerline-status
Find the location
$ pip3 show powerline-status
It shows that the powerline-status is installed at /usr/local/lib/python3.6/site-packages
To activate powerline, you need to source powerline.sh in your .bash_profile
Open up your .bash_profile in Vim or any editor
$ vim ~/.bash_profile
Paste this code into your .bash_profile
# Powerline
powerline-daemon -q
POWERLINE_BASH_CONTINUATION=1
POWERLINE_BASH_SELECT=1
source /usr/local/lib/python3.6/site-packages/powerline/bindings/bash/powerline.sh
Now, create a configuration directory for powerline in your home directory and copy the config_files/ directory from the powerline direcory.
$ mkdir ~/.config/powerline
$ cp -r /usr/local/lib/python3.6/site-packages/powerline/config_files/ ~/.config/powerline/