The primary source of free Gold Coins while playing at Lucky Hands is the Daily Bonus.
Once your account is verified, simply log in each day to claim your reward. The bonus resets every 24 hours from the time you last received it, so you can come back the next day for another batch of Gold Coins and Sweeps Coins to keep the fun going.
To obtain your Daily Bonus, a pop-up on the left menu will appear on the screen if you are eligible.
Or you can click "Wallet" and then select the "Daily Bonus" tab.