We preset your location to the current location of your mobile device. This is automatic, as long as you accepted the prompt when you first installed the app.
If you're visiting a different location, you can change the search area by visiting an events category, then clicking the title (which will ready "Manchester" for example)
A menu will then appear and by clicking on the current location, you can type in an alternative. You may also want to change the search distance, using the slider below.
Once you're done, if you want to return to your current location, repeat the above but click "Use current location"