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Although it is tempting to reach out directly to companies to find gigs, most jobs come through third-party modeling agencies. These agencies partner with companies to supply them with models. You should register yourself on the website of these agencies before approaching the companies themselves.  Some reputable modeling agencies include Fusion Event Staffing and Cosibella Promotional Modeling.  Find modeling agencies in your area by asking local models that you have met. You can also find them by using internet search engines and using terms like "modeling agency" with your city name. The next place to discover real modeling gigs is craigslist. This is especially helpful for finding work in your local area. Look in the sections titled Gigs, Talent, or Job, and search for positions such as “brand ambassador” and “promo girl.” You can use other classifieds websites like Bookoo.com and Freecycle.com, as well as searching the classifieds section of your local newspaper in print or on their website. Facebook is a convenient forum for gathering people of like minds. Joining Facebook groups in your area with “promo girl” or “promotional model” in the title will most likely list promotional gigs quite frequently. For example, search for a group title like “Brand Ambassadors of ________”, inserting your city name. If the group exists, you will likely find plenty of work right in your town. You can of course always use good old Google to find local gigs. Use search terms like “promo girl” and “brand ambassador” followed by the word “agency” or “company.” It’s always best to apply to agencies, not directly to companies, since companies outsource their modeling hires to these agencies. There are also portfolio websites where you can post your information for agencies to look up. Just fill in a profile with one of your prepared photos, and agencies might reach out to you.  Websites like Model Mayhem and One Model Place are popular portfolio database websites. A profile should include a good head shot, your age (important for when agencies look for specific ages), your measurements, personal website, location, information about your experiences and what you enjoying modeling for, and others things that the website prompts you to enter. Instead of focusing on networking with agency managers, look to other promo models to help you find work. Although some models might not give you a referral because they fear losing work themselves, many will be happy to tell you where to find their booking agencies. Ask other promo models who helps them book gigs and whether you should fill out an online form or contact the modeling agency manager directly. Remember, this is not the same thing as talking to a company owner—you are looking for the agency who books the models, and whether or not this agency can be networked in person. When applying for direct positions you have found in your job search, have a cover letter ready to go with your resume. This letter should include details like what things you do to remain professional, why you are easy to work with, and what makes you a good promotional model.  This goes for both internet and in-person applications, although it is likely most of your applying will be done online. If you are headed to an event where different companies and promo models will be present, it is wise to bring along your resume, cover letter, and promotional photos. Then you can hand them over if you get the chance to meet a modeling agency manager.
Register with marketing agencies. Look on craigslist for modeling gigs. Join Facebook groups. Browse the Internet. Create a profile on modeling websites. Network with other promotional models. Be professional when reaching out.