I believe that the way to become a good healer is to practice as a healer, and the way to practice as a healer is to heal in instances--killing things outside of instances doesn't generate the same sort of healing needs.
So we put together a team for Ragefire Caverns. The team was my level 19 paladin (as tank), Lori's level 14 druid, a level 14 shaman, and a level 22 hunter who was unfamiliar with instancing. I was slightly over the target level for the instance--but I think that was pretty good for Lori's first instance. It meant that my healing needs were a bit easier to manage, but healing still mattered.
The run was very successful, with only one wipe to demonstrate that healing really mattered.
I think that Lori has now had most of the quintessential healing experiences:
- she's run out of mana and had to fret and hope she regained enough mana for another heal in time;
- she's been so focused on the tank that she only noticed that she was taking damage and needed to heal herself at the last minute;
- she's had the tank need to buy a 1-handed weapon before going into the instance (in my defense, I did have a shield; I just hadn't received a 1-handed sword as a quest reward in 10 levels);
- she's had her tank run out of the range of her heals;
- and she's felt guilty for a wipe that wasn't her fault. (Someone else pulled in a second group of 3 while we were already fighting one group of 3. 6 foes at once is at the 'you are not expected to handle this' level.)
She's felt very guilty over letting me get out of healing range, particularly since it occurred during the wipe. I have tried to reassure her that every player has made more dire mistakes, but she is eager to play perfectly. I invite you folks to reassure her by commenting with stories of your own dramatic and entertaining errors.