To use dynamic location insertion in Responsive Search Ads, follow these steps:

1. Write a new headline or description in an RSA.
2. When ready to insert the location, hit the { open bracket to trigger the prompt.
3. Select location insertion from the drop-down menu.
4. Choose the type of location you want to highlight (e.g., city, state, country).
5. Optionally, include default text for cases where Google can't insert the searcher's location.

The ad will automatically customize to the user's location, such as displaying "proudly serving Boston" for a searcher in Boston.

To optimize your Google Business Profile (GBP) for local ads:

1. Claim and complete your GBP: Ensure that your profile is claimed, complete with accurate information, and kept up to date.
2. Link your GBP to your Google Ads: This allows your text ads to display your business address and current hours to local searchers.
3. Enable location assets within your campaigns: This can lead to your GBP showing as a sponsored listing in the local map pack with additional text.

By optimizing your GBP, you improve local SEO and enhance PPC results by providing searchers with useful information directly in the SERP.