Standard aircraft? Are you talking about a 4 channel R/E/A/T plane?

To turn a plane we need to bank the wings in order to redirect the lifting force in the direction of the center of the turn. This is done with the ailerons and maybe followed by the elevator.

On many planes this is done more smoothly by adding rudder to the ailerons. This is called a coordinated turn.

On some planes you can just hold that bank and the lift of the wings will take the plane around the turn. However the more standard approach is to now apply a little up elevator which will increase the angle of attack of the wings and take the plane into the turn.

This is sometimes referred to by various names, one of which is bank and yank. The rudder is not an absolutely necessary part of this process, but it does help on some planes. Depending on the plane, sometimes the rudder is actually applied opposite the aileorns to counter adverse yaw. I understand the Piper Cub calls for this, though I have never flown one personally.

If you have a computer radio you may wish to use the aileron/rudder mix to add some rudder to the ailerons automatically. This is one of the benefits of computer radios. This does not prevent you from adding more or takeing the rudder out by using the rudder stick duing the turns. On my aileron sailplanes I have between 25% and 40% rudder mixed to the aileorns. This is on a switch so I can turn off the mix if I wish.

I would not use a Y cable but perhaps someone else knows of this as being an advisable practice. I know in the days before computer radios, there was a slide tray mechanism that was used to mix rudder to ailerons.

Hope that answeres you question.