The e_marketing plan is built exactly on the same principles as the classical plan. There is no different approach, but there might be some formal differences given by the uniqueness of the internet environment. Many of these differences come from the necessity to ensure a high rate of responsiveness from the customers, since the e_world is moving faster and requires faster reaction from its companies, compared to the traditional offline marketplace.
You need to itemize your budget with breakdowns for advertising and promotions. Include any design, development for needed materials to facilitate the marketing. List the media outlets that will be used to execute your marketing plan and break out the online, social, e_mail marketing, e_brochures/e_catalogs, TV, print, radio, PR, tradeshows, sponsorships, philanthropic partnerships, direct_mail, telemarketing, and other outlets. I would also identify which components that will be completed in house and whether you will have an outside agency to help with your media buying and planning.