Some best practices that I follow:
- Don't break down tasks to a microscopic level before adding them to the Gantt Chart, your Gantt chart should be more or less a graphical representation of your WBS
- Try to have an up to date version of the Gantt Chart on the company's Intranet at all times.
- Have only one person update the Gantt Chart.
- Use dependencies and use them wisely (differentiate between lag and float / start to start and finish to finish tasks)
- Try not to change the default settings for the Gantt Chart in MS Project, for these settings are the most used