Attend a monthly Match.
It doesn't cost anything to come out and watch. While you're there, don't be afraid to talk to the shooters. Unless it's a small group, there is generally someone who can break away to answer any questions you might have.
Do your research.
There's plenty of information on the web. Check out a number of different YouTube Channels to see what some of the local clubs are doing. Check out the SASS New Shooter's Handbook. (There's a link below).
Don't Buy Anything!
The biggest mistake New Shooters make is buying before they know what NOT to Buy. After talking to a couple of shooters and doing some research, ask around if anyone is Selling anything! Someone is always buying something and someone is always selling something. Most Cowboy Action Shooters will tell you what is good & what is bad about about what they're selling. But most Cowboys can sell a beaver a fuzzy tail. Buyer beware!
Make a friend.
Find someone to help you get into the game. Cowboy Action Shooting is as much about making new friends as it is about shooting. Now's a good time to start.
Attend a Monthly Match.
This is where you're going to learn. Check with the Match Director. Let them know you are just starting out. They will most likely assign someone to you, unless you came with someone they are familiar with. Don't try to impress anyone, just be safe. They'll invite you back.
Shooters compete in different categories, with special attention to the Children, Young Teens, and the Ladies. While Special Matches (Annual, State, Regional, or National) may award Plaques, Buckles, or Trophies; No Cash Prizes are awarded to participates at Cowboy Action Matches.