King and queen versus king and knight.

Mating with queen against knight was biggest problem for me a while back. It seemed impossible to get opponents king to the edge of the board. But today against Fritz 12 while I was waiting my opponent to move and using Jeremy Silman's complete engame course as guide I suddenly nailed it!
 
1. Make a box with a queen for a opponents king. Make it as small as possible.

2. Don't walk into fork. It's okay if knight threatens either king or queen but not both. 

3. Take notice that being one square diagonally away from knight or two squares diagonally or horizontally is where it takes longest time for knight to threaten you.

Here are my annotations.

I wonder what happened since last time I tried?

Maybe I am not as nervous. The keyword here is patience. The way to resolve this is to concentrate on key ideas and not worry about making sidesteps.