Final answer:
To create a successful ad, select a product, understand its purpose, identify the target demographic, create a catchy slogan, and choose an appealing advertising technique.
Step-by-step explanation:
To design an effective ad campaign for a product, you first need to choose the product and understand its purpose and usefulness. After selecting either bubblegum or a backpack, identify the target demographic, considering factors such as age, gender, and interests. Next, create a memorable slogan that captures the essence of the product. Finally, select an advertising technique from those you've learned, such as bandwagon, testimonial, or glittering generalities. For example, if promoting a backpack to students, the slogan could be, "Carry on with Confidence," and the chosen appeal might be a testimonial from popular students or athletes to influence peers.