I just starting riding clipless this week after two years of deliberating. My best advice would be don't think too much. I was surprised by how easy it actually is and I am not very coordinated at all. It doesn't really matter what position the pedal is in when you clip in and out. I find that I can clip in with my right foot, start pedaling and clip in with the left as I am moving along. When I stop I clip out with my left foot first. I really did not need much practice at all to get the idea it just feel like a natural movement to get the left foot in.

Now given how easy I found it I did get a bit over confident and fell at the end of my driveway on my return home. I did a 30 mile ride and pulled into my driveway to check the cyclometer. I was so focused on the cyclometer that I forgot to clip out and crashed on my left arm. I have my first case of road rash but I survived and will be back out with my clipless pedals again.