Start by downloading the Geocaching app from either the AppStore (iPhone) or Play Store (Android).
Open the app and either sign in or create an account. Follow the prompts after signing in. Make sure to allow the app to use location services when it prompts for them.
Once you finish going through the initial sign in prompts you'll have a map of the area with some caches dotted around it pictured below.
Touch a cache, then select the name of it from the bottom of the screen.
Touch navigate to get directions to the cache. Once you've arrived at the cache try to find it! Some caches have puzzles to solve. If the cache has the option to get a hint feel free to use it!
Once you find the cache touch "I found it". In the app. Take a picture of yourself with the cache and then place the cache back how you found it.
The person that finds the most caches by the speaker jam cutoff time will be the winner!
In order for your cache find to count you must have marked it found in the app and have a picture of yourself with the cache timestamped at around the same time as it was marked found in the app.
Below is a short video guide provided by Geocaching.