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!

Excellent answer already. I would also add 1) Make use of the free training resources on this topic, it is usually a topic discussed in depth 2) Design and test your ads (in particular, are you successful with generating leads, making direct sales?- ensure that your spend and timing is sufficient for the tests to be representative) 3) Design your sales funnel and update your freebie offerings/lead magnets - adjust them as needed to get to the sales conversion you are looking for 4) if you find out that targeting is not working as you wished, try LinkedIn and Google as alternatives 5) be aware that Facebook does a lot of optimization in the first few days and as you test you want to ensure you can cover this time period with your ad

Some insights can be:
- Maybe you find out you need a certain minimum spend to convert to a sale
- Maybe you find out that you can sell the product not directly well over facebook, but if you ask for an email address in return for a freebie, you get a qualified lead

Please feel free to arrange a call any time for more tailored advice

The best person I have found to really understand Facebook Ads from a numbers standpoint (and success rate) is Gabriel St. Germain.

https://www.youtube.com/c/gabrielstgermain

His channel focuses on e-commerce strategies, but gives you the nuts and bolts of understanding the backend to Facebook ads to really understand if you are targeting your customer successfully and gathering the proper metrics for your campaigns.

Let me know if you have any further questions!
Justin