Oh, it is not hard at all. I used to be scared, too. But once I started...there was no stopping me. You can get 'blank' bodies directly from Tonner in DeeAnna's size for about 40-45 dollars but at times you can find a nude dolly even cheaper. The easiest way (if you are patient) to do the heads is with a heating pad that has a cover. I use a medium setting and wrap up the head area for about 15-20 mins until they are soft. Then they just pop right off and are pliable enough to swap out. If they begin to harden again, just warm them back up for a few minutes.
You can use the boiling water method as well if you are in a hurry, but hot water will mess up a hairstyle and remove curl if it gets on the hair.
I don't trust blow dryers...I have had them melt hair before.
Thanks and best wishes!