Ok.  Since I've been undergoing the same labor for some time now, I can tell you what has helped me.  It's really all about pivot points.

1. Start with whichever finger is the most wiggly.  That's usually the middle finger or the ring finger.

2. Move your hand up the neck until your wrist is resting ligthly against the body of the violin.

3. Place that wiggly finger, pointy end down on a note on the A string.

4. Place the thumb lightly, on the side or somewhat under the neck so that the violin is being held by the chin and just the friction of the thumb print against the wood. You should NOT be squeezing anything, the violin is just resting on the thumb.

5. Make sure that the hand is not touching the neck anywhere other than the thumb by making a nice C shape with the hand.

6. Bend the wrist backwards while allowing the fingertip at the first knuckle to collapse backward toward the scroll.  Apply only enough downward pressure to keep the finger from moving out of position -- no more.

7. Bend the wrist forward returning the fingertip to it's upright position.

8. Repeat.

9. Use a metronome and do the same thing for each beat of the metronome.

10.  Once you can do that (which will likely be several weeks) do 2 for each metronome beat, then 4, then 8 and so on. 

11.  Repeat the process for each finger.

This process may take several months.  Eventually, you will have developed the proper feel.  At that point you can do the same thing at other places on the neck.  The purpose of putting your wrist against the body of the violin is to prevent the tendency for the wrist to move forward rather than the hand moving backward which gives the feel of vibrato without actually producing any.

I'm sure you've watched FM's videos on vibrato. Watch these as well: