Feral Cat Taming

So, for the past couple weeks, a young cat has been hanging around my backyard. He's gorgeous, black with a white chest, underbelly and paws, and the most beautiful mint green eyes I've ever seen. He's pretty much an exact copy of the older cat (we assume to be his father) who used to reside in the woods next to my house. I've decided to name him Dexter, and I've been attempting to tame him recently. Unless it's raining (which it's starting to do a lot) he's pretty much always hanging out inside our fence. He's gotten along well with our dog, and has exchanged a few interested glances with my cat from behind the pool cage.

He is, however, very shy with people. I've been leaving cat food out on our deck for him which he never fails to find and inhale. I talk to him, try to acclimate him to sudden noises and movement, and he's gotten a little better. But he still doesn't like me close.

He has been feral his whole life. When he was a very small kitten he visited us a few times. He is now getting older and I think it would be in his best interest if he was domesticated, fixed, brought to a vet and brought into a home.

I've considered setting up an elaborate trap including a dog kennel and a piece of string, but would rather have him approach me first rather than cause him undue stress and force him into something -- potentially causing more skittishness.

Does anyone here have any tips on how to make domesticating a cat quicker and easier?