How firm/tight are your pedals set to.
The firmer/tighter the cleats are held in the pedals, the harder it is to clip them in as more force is needed to push the cleat home.
You could try ajusting the setting on the pedal so that the cleats are held slightly less.
I endded up setting mine to the easiest possible setting to clip/unclip and now I rarely have a problem clipping in and I've never yet to pull a cleat out of the pedal under load.
Also at that setting it putts a lot less twisting force on my knees when I unclip.
It does not make that much difference if I only unclip a couple of times on a ride, but it does make a difference if you constantly unclipping/reclipping as you do a lot of stops, gates, etc, etc, by yourself.
Also try and get a feel of how it feels right before the cleat slots home.
The better you can reproduce that feel, the easier it is to clip in.
You basicly training you musles to get it right every time, so you don't have to think about it.
It took me a couple of month working on it to get it right, but now its so easy to clip in.
Luck ...........
