Here are some tips on how to measure the effectiveness of your billboard ads:

1. Track your website traffic – Use analytics tools to see if there is an increase in traffic to your website after your billboard ad is launched.

2. Monitor your social media engagement – Keep an eye on the social media interactions you receive after your ad is launched.

3. Conduct surveys – Ask customers if they saw your billboard and if it influenced their decision to visit your business.

4. Track sales data – Monitor your sales data to see if there is an increase in sales after your billboard ad is launched.

5. Use call tracking – Use a special phone number on your billboard ad to track how many calls you receive directly from the ad.

By using these methods, you can evaluate the effectiveness of your billboard ad campaign and make adjustments for future campaigns.