Hey Arun,
Many students have similar concerns as you do. But it's really quite straightforward.
First, remember that PMI doesn’t require you to have the official job title of “Project Manager.” What matters is that you’ve been performing the tasks related to managing a project. So that's things like planning, resource allocation, stakeholder communications, monitoring, and control. If you’ve been doing this for at least three years (or 36 months), then you’re pretty much on the right track.
In terms of documentation, PMI relies primarily on the information you provide in your application. But... you want to be 100% truthful, because you might get audited. And it's only at that point when you’d need to be able to back up your claims. Or rather: the contact persons you name in your application for each project have to confirm (electronically) that they agree with and support what you included in the application.
Partial involvement is okay. It’s not necessary for you to have been involved in every single process area on every single project. The key is that across all your projects, you can show experience in each of the five process groups—Initiating, Planning, Executing, Monitoring & Controlling, and Closing. Your experience with vendor coordination, requirement gathering, and project closure should more than likely be sufficient if you can clearly describe the roles and responsibilities you held. Also, managing promotional launches end-to-end definitely sounds like “traditional” project management, in the sense that you’re moving from concept to completion while juggling resources, risks, and deadlines.
As for repetitive or cyclical campaigns, you can list them as separate projects on your application if they happened in different time periods or had significant variations in scope or objectives. On my own application, for example, I submitted at least 4-5 "Web development projects". No issues whatsoever.
Until Next Time,
Cornelius Fichtner, PMP, CSM
President, OSP International LLC