Go to auditions. What new actors need more than anything is experience. You'll probably have to start off by doing free work, but you'll gain experience and be able to add each role to your resume. For example, if a local car dealership needs a commercial, volunteer to be in it. Go to local colleges and audition for their plays or student films. Doing these free projects will build your resume and get you into the habit of auditioning and performing. There is no better way to learn how to act than to actually act.
