Keeping your Director install up to date is important in order to have the most stable, secure version of DIrector possible.
The first step to upgrading is finding out what version you have installed now, as upgrade instructions will vary depending on what version you are using. To do this, login to your Director install and look in the footer for the version number of your current installation.
If you are running version 1.4.x or higher, you can use the in-app updater to download and upgrade your installation. You will be alerted to new versions both on the Snapshot screen and at the top of the System info page.
If you are running version 1.1.x, 1.2.x or 1.3.x, follow these instructions.
If you are running any version between 1.0 and 1.0.9.9, you will first need to upgrade to 1.1, then you can upgrade to the latest version.