Even though it is perfectly acceptable and is a common practice to use the 8_stage classic model for the e_marketing plan as well, you might want to consider the simplified version proposed by Chaffey, who identifies four major steps to build the e_marketing plan:
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.