Start by setting up the 3 ball as the 3rd ball out from the side pocket, on the short centerline of the table.

The 3-1 combination should be aligned straight into the corner pocket. If there's too much throw on your balls, twist this to the right side of the pocket. The 2 ball is frozen to both the 3 and the 1 ball.

As you can see in the first picture, I place the cue ball one ball width out from the diamond. I aim >1/2 ball hit on the 3 ball with 1/2 tip draw and 1/2 tip right. Adjust the draw to get back to the ball hanging in the corner. The right helps throw the 2 ball in. Only make slight adjustments to adjust for the bank angle (moving the cluster left or right). It doesn't take much to get it to go.