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.
Defining strategic objectives: the organization must have a clear vision and establish if the media channels will complement the traditional ones, or will replace them. We must define specific objectives (don't forget to check if they are SMART!) and we must also specify the contribution of the online activities to the organization's turnover.