Quarterly ad planning should involve setting a budget and goal, research to determine the target audience, choosing the appropriate ad platforms, developing an ad strategy and creative, executing the ad campaigns, and finally evaluating the effectiveness of the campaigns.
For example, a quarterly ad plan for a new product launch could involve setting a goal of driving new product sales, researching the target audience to ensure the right message and offer is delivered, choosing the appropriate ad platforms such as Google Ads or Facebook Ads, developing a strategy and creative to be used in the campaigns, executing the campaigns on the chosen platforms, and then monitoring the performance of the campaigns to evaluate the effectiveness of the ads.