If you are analysing your data, or just know your customer well, you will know that certain areas provide better customers than others. It is logical then to want to pay more in this location than others.
The above video shows how to add a location bid adjustment, this means that any bid that you have entered for any keyword, this will be raised or decreased (depending on what you have selected) by the percentage you put in.
In order to do this, you need to add the location first (in your location targeting), then depending on the data you increase or decrease by a percentage. If you are not sure where this data can be found it is in the dimensions tab and then user location.