Pretty good tip I found here!
“To enable smart completion, edit your /etc/bash.bashrc file. Uncomment the following lines, by removing the # in the beginning of the lines:
# if [ -f /etc/bash_completion ]; then
# . /etc/bash_completion
# fi
Now you can use tab completion to power your way through commands.”
You could edit ~/.bashrc instead if you don’t want to make it global.