After you’ve put together your project plan, and whenever a change in scope, resources, or time can affect the project completion date, you should evaluate and then adjust your schedule.
Evaluating your schedule will give you an accurate picture of what you may need to adjust. Make sure that your schedule contains complete and accurate information, models your project realistically, and meets your project goals as efficiently as possible. Then, adjust your schedule as necessary.
You should follow two major steps to evaluate and adjust your schedule. First, make sure your plan is accurate and complete. Take a high-level look at your project plan. Does it meet project goals? Does it include all necessary tasks? Are your cost, duration, and work estimates accurate? Did you enter any erroneous information, such as assigning the wrong resource to a task?
Second, streamline your plan if possible. Take a close look at your project plan. Is your plan as lean as you can make it? A lean plan includes only the tasks necessary to accomplish your goals. It uses resources efficiently, ends on the earliest possible date, and costs as little as possible.
This chapter spells out a number of key ways to make your plan accurate and complete. It also summarizes the actions you can take to streamline your plan, such as shortening your schedule and reducing project costs. For more detailed information about how to streamline your plan, see chapters 11 to 13.
If you regularly save each version of your project under a new name, you can easily revert to the previous version. For example, you can include the current date in the name of each version of the project file: Plan7-9, Plan8-9, and so on.