The overlap must be only set, if you are using a new focal length. If you already have created a panorama with your desired focul length, then you can simple choose this as preset and skip the overlap settings.
Each time you create a new preset, you will be asked for camera model, lens and focal length. This way it is ensured, that you use always the right configuration according your current setup.
Depending on your desired scene, you have to choose a suitable motion pattern. The panorama mode offers a vertical and a horizontal motion pattern.
The horizontal motion pattern is suitable mostly for scenes where you have a sky. If you have moving clouds or changing light situations due to the sun going up or down, you want to choose horizontal movement. This way, the sky will be captured first and will have a consistant exposure.
The vertical motion pattern is suitable, if you want to shot panoramas with a very high pan angle. The vertical movement has the advantage, that you can step out of the field-of-view very easy. If you would do a 360° panorama with the horizontal movement, you would have to pay attention multiply times to avoid the field-of-view of the camera.