Rearrange and rename alpha and spot channels

You can move alpha or spot channels above the default color channels only if the image is in Multichannel mode.

To change the order of alpha or spot channels, drag the channel up or down in the Channels palette. When a line appears in the position you want, release the mouse button.
Note: Spot colors are overprinted in the order of their appearance from top to bottom, in the Channels palette.
To rename an alpha or spot channel, double-click the channel’s name in the Channels palette, and enter a new name.

Photoshop