Make Sure You Have Java
java -version
Enter /usr/local/bin
cd /usr/local/bin
Get the Magical Lein file
curl https://raw.githubusercontent.com/technomancy/leiningen/stable/bin/lein > lein
Allow the Lein File to Be Executed
sudo chmod a+x /usr/local/bin/lein
Ensure /usr/local/bin/ Is In Your $PATH
echo $PATH
vim ~/.bash_profile
Run Lein (While Inside of /usr/local/bin)
lein
Celebrate!
lein version