I need to copy an icon from a design that has a vector mask in photoshop.
How can I do it so I get the icon to paste exactly as I see it in the design, so it can (for example) be added to a css image sprite and used online.
To duplicate it to a new document, right click the layer and select "Duplicate Layer". Choose the destination document you want to paste the layer into. The vector mask will stay with the layer when it is copied.
If you want to duplicate it within the same document, just drag the layer onto the new layer icon at the bottom of the layers panel.