In this tutorial you can learn how to hockey stop on the ice.
For animations and additional stops, check out the Youtube video linked below.

Step 1: Start Turning From Slow Speed

The safest way to learn a hockey stop is from a low/moderate speed.
In the picture above, we are turning left, meaning that the right ice skate's inside edge will contact the ice during the stop. You can use the left leg for support.

Step 2: Start Rotating Your Foot Around the Pivot Point

Memorize the yellow cross. That will be the pivot point. You'll start turning around that point.
Shift your weight a little bit towards the nose area to allow free movement for the heel for the right leg.
Remember if you start to loose control, use your left leg for support.
If you go faster later on, you can lean in otherwise you'll fall over to the other side.

Become confident with the drifting feeling then move on to the next step.

Step 3: Speed Up the Process

Try turning into the final direction more and more quicker. You can push your legs ahead this way you can enter the backwards leaning position swiftly (as seen in the pic above).