In a project of any size the sheer number of things that need to be done can be overwhelming. One tool that a project manager can use to get their mind around their project is to create a work breakdown structure (WBS) and the corresponding WBS dictionary. A WBS is a deliverable-oriented grouping of the work involved in a project that defines the total scope of the project. The dictionary is a document that describes in detail the information needed for anyone to understand what each WBS item is.
There are many methods for going about the creation of a work breakdown structure including: the analogy approach, mind mapping, top down, bottom-up or just using the guidelines established by your company.
Regardless of the approach, the WBS should be created in conjunction with the team members who will be working with you to produce the project deliverables. This may be as simple as a meeting where everyone gets a stack of post-its and contributes their knowledge of how the work gets done by writing down their tasks and sticking them to the white board. This exercise also helps give the entire team an understanding the project purpose and scope while at the same time getting their commitment and buy-in for the work that needs to be done.
Check out this short video by Rita Mulcahy, PMP, as she addresses the concept of the WBS: