Dynamic remarketing allows businesses to show personalised ads to users based on their browsing behaviour on a website. With Google Tag Manager (GTM), you can manage the tags that collect and send data, such as product IDs or page types, to Google Ads. This ensures that visitors are retargeted with ads for the specific products or services they viewed.

To set up dynamic remarketing, you need a Google Ads account with remarketing enabled and a Google Merchant Center account for e-commerce businesses to upload product feeds. Google Tag Manager must be installed on your website, and a properly configured data layer is required to capture dynamic parameters like product IDs and page types.

In GTM, you can create a Google Ads remarketing tag by logging into your GTM container, adding a new tag, and selecting "Google Ads Remarketing" as the tag type. You then enter your Google Ads conversion ID, map custom parameters like product IDs using data layer variables, and set the trigger to fire on all pages or specific events depending on your campaign needs.

Common mistakes include forgetting to link Google Ads with the Google Merchant Center, failing to set up a data layer for capturing dynamic parameters, using outdated or inaccurate product feeds, and not testing tags in GTM preview mode or verifying them with tools like Tag Assistant.

To comply with privacy laws like GDPR and CCPA, you should use consent management tools to obtain user permission for tracking. Ensure the data collected and shared with Google Ads is anonymised and secure, and leverage first-party cookies while avoiding the collection of sensitive data without explicit consent. Tools like CustomerLabs Sentinel can assist in managing privacy compliance effectively.