While on the Station list, swipe your finger across the station name, then tap the red ‘Delete’ button that appears.
 
A second method to deleting a station while on the Station List is to tap the station you would like to delete, then tap ‘Options’. A menu will appear where you can choose to ‘Delete Station’.
 
If the station you want to delete is on the Now Playing screen, tap the back arrow button in the upper left hand corner to return to the station list and following the preceding instructions.