A documented project plan can help to expedite the implementation of your disaster recovery procedures by identifying and coordinating pre-requisite tasks, responsibilities and resources for each task.
Pre-planning allows for many questions to be answered before the actual work begins,preventing delays and redesign during the implementation.
A project plan allows for the breakdown of tasks into more manageable chunks so that the overall project is not as overwhelming. The project plan helps to define and validate the solutions, and more importantly help you manage and coordinate the rollout.
Consider your options and be sure to account for the protection of your applications and systems as well as infrastructure and human resources.
Although you likely have many systems and applications running throughout your company, they are not likely all of the same importance to the success of the business. Determine and document what systems and data are critical and focus on those first.
Some systems can probably be down without adversely impacting the business while others are more critical and must be brought back online quickly to prevent losses.
Simply applying the same levels of protection to everything can leave some systems insufficiently protected or prevent the plan from ever being implemented as costs and complexity will be insurmountable barriers.
Your project plan will be a living document, continuously reviewed, updated, and modified as the implementation progresses.