1. Pin the extension so it is always one click away
2. Click the SERP Checker icon, the side panel opens next to your results
3. Type a country, a city or a full street address and pick it. That single click switches the extension on and reloads Google for that place.
Tip: the radius slider is how precisely you claim to know where you are. Exact means that one address. Widening it only changes what Google shows once the circle covers a whole region, which we measured rather than guessed.