It takes a lot of work and energy to tame a kitten. For my opinion on taming adult cats, please click here.
I agreed to tame Gracie because she is 3 months old. At 3-4 months old, it is possible to tame them. It isn't easy, though. Taming (among other things with kittens) requires patience, energy, time and space.
My job is to get her used to be around humans, get her comfortable around the noises she will hear in a household (such as vacuuming) and begin to enjoy being around us. Gracie is not considered feral. She is very shy and very skittish. She is just a "hard stray". She is a stray cat that requires a lot of work to get her to be like a normal house cat.
Using baby food helps immensely. I have noticed with all of my ferals, they are the most nervous and skittish when you are walking towards them or around them. They run and hide. I am trying to show her that she will not be hurt if I walk by her. So, I carry around baby food and walk to her and give her some baby food.
I sit with her to lure her to my lap with baby food. Once she gets some baby food, usually she will lay on my lap and let me pet her. Sometimes she will snatch some baby food and run away to play with the other kitties. She purrs and rolls around so I can scratch her belly. Taming is a constant process. You can't really tame them once a day, or even twice a day. You have to keep on them and keep challenging them.