If you are planning to start facebook ad, first keep one point in mind. When ever where ever we spend money on marketing and promotion we must track the result for amount we spend. With out tracking perfomance if we spend it is like burning cash with out knowing.
So to get best result from facebook ad, first of all add tracking code in your website then run faceboook ad. So that from day one you can track your ad perfomance.
Always target right audiance in fb. As fb is like sea where core and core people just vist to browse and chat with friends. Dont have idea about buying your product or service. They all time passer so if you shown your ad infront of them no result you will get.
So set a audiance and target only them. Try facebook whatsapp message converstion type ad. So that when even people intrested in your product or service you will get alert in whatsapp. So easily you can monitor the perfomance also you will be charged per conversion. So easily you can save money also.