I found this site with a software for designing Crochet patterns.
Just click on the link >http://www.crochetdesigns.com/
Here are some Instructions on how to create your design.
Decide the kind of item for the pattern. This can be an afghan, sweater, doily, cap or any of the many things that lend themselves to crochet.
Use a pattern template. Any crochet pattern you create will provide the template that shows exactly how to set out the pattern so others can follow it. Simple software for designing patterns on a computer is also available at a reasonable price.
Crochet the item. Every time the stitch changes, stop and make note of it in the template. This can be done by making notes on paper, then typing into the template or software later on.
Create the item a second time once all the steps have been entered into the template. This time, follow your own written pattern instructions to the letter. Make notes of any errors in your pattern, then correct on the official pattern or software.
Take a photograph of the finished product to go with the pattern to help sell it. Patterns can be sold on various Internet sites or through local craft stores and craft fairs.