There is a nine trick
First, you hold up all of your fingers
So if you're doing 6x9, you would hold up your 10 fingers, and count to six, while each number, hold a finger down. When you're done, you should have the thumb of your right hand down. So since your left hand has 5 fingers down, that's 50. Next, you skip your thumb and count 4. That's 54
6x9 is 54