Regularly review estimates, deadlines and milestones to check they are still on schedule. If necessary, update the plan with new estimates and tasks and ensure that remaining tasks are necessary and estimates are still valid. Circumstances can change during a project but question every change and always refer back to the original business requirement as a corss-reference.
A Critical Path Analysis diagram uses a linear timeline to identify dependent tasks and is particularly used on large, complex projects which may have hundreds of dependent activities. These diagrams highlight dependent tasks that overlap and, therefore, require adjustments to the schedule.