I have not worked with Gantt charts in industry, though I have during my senior design project in developing a neuro-prosthetic arm. The first factor to understand is to know the relationships between tasks in terms of their dependencies on one another. Normally, tasks are connected on a Gantt chart under a Finish-to-Start relationship, which states that a predecessor task must be completed before a successive task can be initiated (a 3D model of the device must be generated before a prototype can be manufactured). The same applies to start-to-start, start-to-finish, and finish-to-finish relationships. An example of a finish-to-finish relationship would be writing up a procedural document while having it edited in that both the writing and editing must be completed before submitting the final document for approval. A start-to-finish relationship can be refilling supplies for a process that is dependent on the supplies themselves, meaning that the start of restocking supplies is dependent on when the process is finished. Finally a start-to-start relationship can be exemplified by relating a writing task (written description of a device’s primary components) with the drawing of blueprints in that the start of drawing blueprints depends on the start of writing. In reality there will be a lag time in between the two tasks since a decent amount of writing is required for drawing blueprints.

An online article about creating a Gantt chart advises certain techniques such as subdividing tasks into subtasks to simply elaborate what must be done (1). Other advice mentioned includes defining the critical path of tasks that the project must take to reach completion, as well as assigning milestones for major events. Can Gantt charts be established in a way that optimizes float time, the maximum allowable time for a delay to occur? How would the use of a design matrix compare to a Gantt chart in terms of scheduling tasks and determining dependencies between those tasks?

Reference:
(1) “Tips for Project Planning with Gantt Charts”, Smartdraw website