Summarize the following:
Start by working in your local film scene or in areas that you can easily get to. Save the money you make so you can make the move to a larger city where more roles are available and movies are frequently made. Consider moving to Los Angeles, Austin, New York, or Atlanta if you're in the United States. Try Vancouver, Toronto, London, or Mumbai for film outside of the US. Search for casting calls on websites like Backstage or Craigslist for local commercials. As you go in for the audition, dress for the part you're playing so the casting directors can easily picture you in the role. Commercial acting is a smaller role, but it will give you exposure to a wide audience and get your face out to the public. Look out for posts on Craigslist that seem too good to be true since they could possibly be scams. Watch for off-site emails or jobs that seem to be paying too high with no needed experience. Once you're where you need to be, get connected and take on roles as an extra, or background actor. Open casting calls for these can be found all over the Internet, but a few places to start off are Backstage, Hollywood Reporter and Variety. Though it may not be a starring role, you can still list an extra role on your resume to show you have experience. Ask around your network for opinions on who to go to and how to get started. Make cold-calls or send inquiry letters to agencies to see if they are looking for new talent to represent. An agent will help you negotiate deals for the roles you take on. Agents only get paid when they find you work. Don't buy into the ones that demand some exorbitant fee even if your schedule stays wide open. Look into organizations like ACTRA, AEA, AGMA or AGVA. Once you are a member for at least 1 year and worked under union, you're eligible to get into SAG (the Screen Actor's Guild). Unions provide you with benefits and insurances while you're working. Annual SAG fees are $201.96 USD and 1.575% of the earnings you make in that year. Check with the union you're interested in to see what their annual rates are. Though it's completely possible to run through all the hoops without it and still find success, having your equity card opens up a number of auditions that otherwise wouldn't be available to you. You either have to get a contract that requires equity standing, be a member of a sister group (like SAG, for example), or accumulate enough credits to meet the standard. It's natural to find the process a bit confusing, so contact a friend or mainstay in your actor's social network for more information on how they received their card.
Move to a large city if possible. Look for roles in commercials when you begin. Become an "extra" actor in larger pictures. Get an agent. Get into a performer's union. Consider getting your equity card if you want to do theatre.