Upgrade to the latest version of OS X if possible
We also recommend installing a good visual git GUI such as Github Desktop.
It's probably a good idea to do some work on your dotfiles to make them nicer.
Option 1 (for the adventurous): go for a git-managed dotfiles setup such as this.
Option 2 (minimal): just make your command prompt a bit more helpful – add this .bash_prompt file to your home directory.
It's OK to install more than one.