To install Ranger on a Gentoo system, you can use the Portage package manager. Here are the steps to do so:

First, make sure your Portage tree is up-to-date. Open a terminal and run:

   sudo emerge --sync

Next, install Ranger using the following command:

   sudo emerge --ask app-misc/ranger

If you want to configure Ranger, you can create a configuration file for it. The default configuration file is located at `~/.config/ranger/rc.conf`. You can edit this file to customize your Ranger settings.

To run Ranger, simply type the following command in your terminal:

   ranger

Here's a summary of the commands you would run in the terminal:

sudo emerge --sync
sudo emerge --ask app-misc/ranger
ranger

That's it! You now have Ranger installed on your Gentoo system.