Now, to chunk a picture is a very simple and useful technique to learn for creating stencils.
Let's just say for instance that you are wanting to create a letter H stencil, you would first break up the picture.
First, you section off pieces that make up the letter H. You will do the the middle as one section, and make each vertical piece a section as well. So, in the end you will have five sections.
The reason this is so helpful is because it will allow you to discard the excess. If you are cutting a big section at one time the part you have already cut will begin to droop and hang and get in your way and make cutting the newer sections, if not harder, more annoying.
Another perk of using this technique is that you can section off the stencil and if you can't finish the whole stencil in one sitting then you can come back to it later.
This technique is very simple. I urge you to chunk your stencils. It will make for a more enjoyable and less annoying time and it will give you the freedom of not feeling pressured to do the entire stencil in one sitting.