First of all, do you want to do it for the money? There are many people who think they can get rich quick selling their designs. In my experience, this just does not happen. It is very difficult to make a living wage selling crochet designs, and I know only a few designers (three, actually) who are actually able to do so. And each of them has been designing for more than 20 years. Even very well known designers usually have a "day job"; or else do not depend on the income from their designs (they have someone else paying the bills).
Many publishers have scaled back the number of crochet books and magazines they put out each year, so it is harder than ever to get something accepted for publication. You have to have a thick skin (which I do not), because you are probably going to have your designs or ideas rejected at some point. I have been designing a long time, and I still get rejected. And when I do, it still stings.
Another thing to consider is the amount of time you are willing to devote to actually crocheting. You have to turn out new designs consistently to be successful; in my case this means crocheting at least 8 hours every day, usually 6 days a week; more if I have deadline to meet. And this goes on year after year. Burnout has been the end of many a budding designer's career.
I am sorry to sound so negative, but I have met so many people who truly (in my opinion, anyway) have unrealistic dreams of becoming a professional designer. I don't want to crush any one's dreams, but I think everyone should be aware of the pitfalls.
But there are many other reasons to become a crochet designer that do not involve being published. There is nothing more precious than a hand crocheted baby blanket, unless it is a hand crocheted baby blanket that has been designed especially for the recipient. While I cannot in good conscience encourage anyone to be come a designer for money or fame, I can, and do, encourage every crocheter to stretch their creativity and create their own, original works of art.
There are a few basic formulas and techniques that make it possible to quickly, and rather painlessly create beautiful, unique and personal designs, and I will talk about some of them in the next post. Happy crocheting!