Take some head shots. Regardless of the particular industry you want to work in, your image is important to a talent agent. That's not to say that you must be stereotypically beautiful, but you must have a "look." If you're seeking modeling work, have a friend take some photos of you with no makeup on. A model agency wants to see your bone structure and complexion. Select three or four portrait head shots and a couple of profile shots. Actors' head shots need to be more diverse. Pick five head shots that demonstrate your range and personality.
Make a show reel. Set up a camera and record yourself performing. If you seek presenting work, give a 30-second to one-minute demonstration of your presenting skills. Use the style of current television presenters to guide your choice of outfit.
Build a website. It doesn't need to be expensive or complex. Having a website means you can direct people to a place where they can get all the information they need about you. Purchase a domain name and hosting from a domain registrar. Install a blogging platform to enable you to update your website with information, photographs and links to video-hosting websites.
Send an inquiry email to an agency. Only when you have all of the material to support your application should you approach an agency. Some agencies limit the contact information they make available to reduce the amount of speculative phone calls. For example, the CESD Agency in New York only has a contact form on its website, with no phone number or direct email. Keep your message brief and include your phone number, email and your website address. Don't expect an instant response. The purpose of the email is to provide the agency with material so they know who you are when you call them.
Make a follow up phone call. Some agencies have offices all over the world. Pick the office closest to you. For example Creative Artists Agency has offices in Los Angeles, New York City, Chicago, St. Louis and Nashville as well bases in Europe and Asia. Your call will be answered by a receptionist. Politely ask to be put through to the person that deals with new talent. Once you're through, clearly give your name and explain that you're calling to see if they have had time to review your show reel and pictures.