Healing doesn't really have a rotation of spells to go through like a DPS spec does, however, there are often certain types of situations that arise where you can respond in a certain fashion. I've detailed some of the most common situations below, as well as how to heal them. In the heat of battle, you may not always be able to stick to these things exactly, but with a little practice they should become second nature.
If you have any questions or feedback, you can leave a comment below or contact me on Twitter @PrestonDvorak.
September 12, 2017 - Added simulation information for Netherlight Crucible abilities and adjusted rankings.
September 05, 2017 - Added Invasion Point gear to best in slot lists.
August 27, 2017 - Added Nether Crucible information to the Artifact page.
August 07, 2017 - Updated the Consumables page to include Feasts and the Mastery neck enchant.
July 29, 2017 - Updated the Best in Slot lists with notes on T19 vs T20 and viability of Tomb trinkets.
July 08, 2017 - Updated Grid settings to include Tomb of Sargeras boss debuffs.
June 15, 2017 - Finished simulations for Large-group Healing trinkets and legendary items - those lists have been updated.
June 13, 2017 - Initial 7.2.5 review. Expect more updates in the coming weeks.
May 02, 2017 - Added "Other Notable Addons" section to the addon's page.
April 27, 2017 - Updated all best in slot lists to accommodate Aman'thul's Wisdom being a top legendary choice.