Learn everything you possibly can about fashion including some fashion history. Also, know the different types of fabrics, patterns, styles and common fashion terms. Make sure you know a lot about fashion and be prepared to show proof of your knowledge and skills. It would be to your advantage to take some fashion classes or even get a degree in fashion merchandising.
Get some experience working in the fashion industry. You can find writing jobs as a freelance writer for fashion blogs or fashion related websites. You can also work as a freelance stylist, which will broaden your knowledge of the different styles, fabrics and fashion terminology. Another great option is to start your own fashion blog and write about fashion trends, events, parties, news, designer and model biographies.
Have a cover letter and resume ready to show prospective employers. Your cover letter should say why you want to be a fashion columnist and why you think you are qualified for the job, listing particular skills or unique knowledge of the fashion industry. Your resume should highlight all of your specific fashion knowledge. Prepare a few writing samples to include with your cover letter and resume. If you don't have any published samples, just write a short piece on current fashion trends to showcase your writing style.
Contact fashion magazine editors or the editor of the fashion column in your local newspaper. The best way to contact editors and show your interest is to email them a cover letter, resume and writing samples to showcase your education and experience. Writing samples should be short pieces on any fashion topic. Be sure to use as much terminology specific to the fashion industry as you can. Let the editors know that you have extensive knowledge of the inner workings of the fashion industry, and will be valuable to their publication as a fashion columnist.
Be persistent, make as many contacts in the fashion industry as you can, and continue honing your fashion writing skills. You may even have to write for free in an effort to get your foot in the door. Breaking into the fashion industry can be quite difficult so be patient. Whatever you do, don't stop writing and learning about fashion because the more you know, the better your chances of getting a job as a fashion columnist.