With the dog next to you say the word "Watch" or "Look",  once she looks say "Good", release the dog, use a word like "Ok" and give her a treat.

Repeat 4 to 6 times and then stop until the next time.  Do this for about a week, some dogs take longer but she should look at you when you say "Watch".

Keep the lesson short and happy, and she will learn even quicker.

With time it should become automatic for her to look at you without a command.

Put your dog on a leash, bring your treats too and go outdoors if you have a backyard take her there, if not just right outside your door, and say "Watch" or "Look" once she looks say "Good",  say "Ok" and give her a treat.  

Repeat 4 to 6 times and then stop until the next time.  Do this for about a week, some dogs take longer but she should look at you when you say "Watch".