You shall follow the steps given below to be an expert in ads on Facebook:
1. You shall have a good understanding of your business niche.
2. Start making ad campaigns that are unique and different from other companies' campaign so that you stand out from others.
3. Try to make creative ads that are related to your business which will engage customers and increase engagement.
4. Use Facebook advertising tools like pixel or ad builder for better targeting as well as tracking.
5. Keep track of all your campaigns so that you can improve them according to customer's needs.

Also remember not to spam users with irrelevant ads or coupons but only advertise products/services related to their interests or hobbies! I hope this answer is helpful!