1. Start the installer: Navigate to the `idlxx-mac.pkg` file that was downloaded to your computer and run it. 2. Follow the prompts to install the software. 3. When installation is complete, license the software. To activate node-locked licenses to a specific user and computer, see [[Manage Licenses From The License Administrator Tool]] for steps. 4. From the Mac Finder, go to `$INSTALL_DIR/idlxx` and double-click `IDLx.x` to launch IDL.