Well at least one answer; and not the magical kind of come to life, but the kind of life that will make that doll stand out from others. And maybe in a way, having a doll stand out does bring it to life magically, to be picked up time and time again by whomever owns it.
Making a doll come to life is all about proportion; how one thing relates to another, size, length, fabric choice. I learned all about proportion in Fashion Design school, it's one thing to learn it and another in practice. It's something that takes time and practice AND trial and error.
I'll show you what I mean, here's a look into my making sketchbook:
This doll looks like a bean. She didn't even get arms because I wasn't happy with the body shape. The for head is too high, not enough space up there for realistic hair. So it threw all the other facial features off.
This doll is smaller and flatter. Good face proportions but she is just too flat. In fact she looks like a drawing. I wanted to do something different for hair so thought an extension of felt would look good, but it made her even more flat. I like the length of her limbs, but her legs are too far apart.
Alien doll ahead....this doll is getting the more 3D look I was going for but the eyes are CRAZY! With the big hair up top, it makes the lower half of her face look too small edging on gaunt/alien like. I put some plastic beans in the bottom half of the body to try to give it more weight, but it ended up spreading the legs apart more. That accentuated the fact that the limbs were too narrow.
I liked the hair, because it is an alternative to felt, which I had been looking for for a while. I wanted something more 3D.
To balance out the big hair I made the whole body and limbs 1/4" wider.
Once I had the body figured out, I had to figure out the eyes. THAT was a journey in itself. Take a look:
So again, the proportions can make or break a design. Eyes #1 were too small, #2 good size, but the tear drop size was too sleepy, #3 not enough character, #4 too animated, #5 the eyes get lost and washed out especially on the fair skin, #6 too bright, #7 sequins are too bright for this dolls eyes, #8 just right!
Here she is all styled and ready to play!