Before you sit at a table
Read the rules of that exact game
Card games with the same name can differ from table to table. The rules page inside the game is the one that counts.
Check the smallest bet
Find the table stake before you join, so one hand cannot take more than you planned.
Know who you are playing against
Some card games are against the house and some are against other players. The risks are not the same.
Use a steady connection
A dropped connection in the middle of a hand can cost you the hand.
Finding your past hands
The side menu has a Bet record page. Use it to check what you staked and what was paid. If a result looks wrong, take a screenshot and go to support.
Not sure the tab is for you? The games page lists the others.