If you are creating a morph-based head, you have to separate the head from the body first.
It should be a front-facing character and the picture should have no glasses on or hair covering the face.
Make sure the background is transparent.
Pick a character template.
Bring the character template to the Composer Mode.
Click Çreate 'morph-based head.
Open the 'face' that you have created earlier.
Follow the instruction given in the Ímage Processing' screen.
YouTube Tutorials Here