First you need a Trakt account (it is free).  Once you have created your Tract account you need to sync it to Exodus

Sync Trakt to Exodus

Hover over Exodus in your video add-ons > press menu (button with three lines) > add-on settings > accounts
Under the Trakt heading, click authorization
You will be prompted to go to the Trakt website listed. Once there, you will sign in with your account and validate the Kodi Exodus add-on and in return, it will give you a code.
Return to Kodi, click Enter Pin, and enter in the code you received.

Kodi Exodus Trakt Features

When Trakt is approved, your Trakt details can be found under the My Lists category in the add-on. From there, you will see a list of options:

Collection/TV Collection – This is exactly like the Kodi library integration, except it syncs with your Trakt account and works across multiple add-ons! You can add a show to your collection in Velocity and it will appear in Exodus and vice-versa.
Watchlist/TV Watchlist – Your watchlist lets you add and keep track of shows you aren’t watching yet but have an interest in.
Featured/TV Featured – These sections automatically pull the featured movies and TV shows from the Trakt website, giving you an idea of things you might be interested in watching.
Movie/TV/Episode Lists – From within the add-on, you can add shows to lists and name them. For example, add movies to a Horror playlist or classic TV shows to a classics playlist and view them here.
Hovering on nearly any movie, show, episode or heading in Eodus and pressing the menu button, click on Trakt Manager to add different things to your collection, watchlist, or a list! With these features, you don’t need Kodi library integration.