Short Stories

So, while I am in the process of writing my book, I feel that it is a good idea to start writing some short stories to be published in various magazines, so that when the time comes for me to submit my book to publishers, I will have previously published works in the market for them to not only read, but so that I will be taken more seriously as an author. I also would like to become part of the Science Fiction and Fantasy Writers Association, which is a group for published writers of the science fiction and fantasy genres. To be eligible for their Associate Membership, you must have at least one published work, novel or short story. To be eligible for their full membership, what they call Active Membership, you must have a published book or three published short stories (equaling a certain amount of money, with a certain amount of words and be paid at a certain amount per word). So, I'm hoping that during my writing process I can become an active member as well, so that I will have as much reference available for when I send my book for publishing.