Click on the Tune in tab.
Make sure Search by is set to tags. How?
The drop-down should have 'Tags' selected.
Type in a type of music you like and click Find it! - a cloud of related tags will appear.
The type of music you've typed in, if it's there, should be selected, you can choose another if you prefer.
The tags you've chose will appear in the bottom left under Your custom station. Click on the green play button in the bottom right hand corner
Tuning into station... should appear above the tabs. Your songs will start shortly