To make an effective plan, there is a famous rule called 4P's. Here, P's stand for Price, Product, Promotion and Placement. In this another P is added called People. Today while doing digital marketing or the traditional marketing one should understand people or the customers you are dealing with. It's important to figure out what is significant for the business, and later make a plan accordingly.
The marketing plan that has a feedback cycle, from 8th stage back to the 4th. That is because sometimes during the planning process, we might need to perform stages 4 to 8 several times before the final plan can be written.