Do one of the following:

• Select the Slice Select tool  and click the slice in the image. When working with overlapping slices, click the visible section of an underlying slice to select it.
• Select the Slice Select tool, and Shift-click to add slices to the selection.
• Select the Slice Select tool in the Save for Web & Devices dialog box, and click in an auto slice or outside the image area, and drag across the slices you want to select. (Clicking in a user slice and dragging moves the slice.)
• Choose File > Save For Web & Devices. In the dialog box, use the Slice tool to select a slice.

Move, resize, and snap user slices

You can move and resize user slices in Photoshop, but not in the Save For Web & Devices dialog box.

Move or resize a user slice

Resize or move a user slice using numeric coordinates

Snap slices to a guide, user slice, or other object

Divide user slices and auto slices

Use the Divide Slice dialog box to divide slices horizontally, vertically, or both. Divided slices are always user slices, regardless of whether the original is a user slice or an auto slice.

Duplicate slices

You can create a duplicate slice with the same dimensions and optimization settings as the original. If the original slice is a linked user slice, the duplicate is linked to the same collection of linked slices. Duplicate slices are always user slices, regardless of whether the original is a user slice, a layer-based slice, or an auto slice.

Copy and paste a slice

You can copy and paste a selected slice within an image, into another image, or into another application such as Dreamweaver. Copying a slice copies all layers within the bounds of the slice (not just the active layer).

Combine slices

You can combine two or more slices into a single slice. Photoshop determines the dimensions and position of the resulting slice from the rectangle created by joining the outer edges of the combined slices. If the combined slices are not adjacent or have different proportions or alignments, the newly combined slice may overlap other slices.

The combined slice takes the optimization settings of the first slice in the series of slices you select. A combined slice is always a user slice, regardless of whether the original slices include auto slices.

Change the stacking order of slices

When slices overlap, the last slice you create is the top slice in the stacking order. You can change the stacking order to gain access to underlying slices. You can specify which slice is on the top and bottom of the stack and move slices up or down in the stacking order.

Align and distribute user slices

You can align user slices along an edge or their centers, and distribute user slices evenly along the vertical or horizontal axis. By aligning and distributing user slices, you can eliminate unneeded auto slices and generate a smaller, more efficient HTML file.

Delete a slice

When you delete a user slice or layer-based slice, auto slices are regenerated to fill the document area.

Deleting a layer-based slice does not delete the associated layer; however, deleting the layer associated with a layer-based slice does delete the layer-based slice.

Lock all slices

Locking slices prevents you from resizing, moving, or otherwise changing them accidentally.