Best method to create your initial gantt chart

1. Define Scope from Top-Down
   • User Stories first. For not just get them into Project.  You can decide later which stories should go together or in a specific order.  
   • Add the ADCRD Loops in EACH user story and indent them.
   • Add in the appropriate tasks under each ADCRD section of the user story.  Make sure you capture all functional and non-functional requirements as well as ancillary tasks that you'll need to complete the user story.  Don't forget to include important steps like test, fix, and retest and deployment and of course any change management tasks.   
2. Then Set Duration per task once you have all the tasks identified.
3. Assign owners per task
   • Don't leave out your client.  Include any stakeholder that's necessary
   • You're allow to assign more than one owner to a task if it makes sense.
4. Dependencies
   • We want to see parallel work when possible.
   • Multiple deployments are expected when embracing an Agile mentality in a project and deploy in sprints (i.e. not all at once near the end).
5. One more tip
   • Careful to avoid ANALYSIS PARALYSIS when building the plan.  The purpose of building the detailed gantt is to help you understand how long each story will take and build out your expected milestones.