Photoshop offers very powerful layer capabilities, which can cause confusion. It is also quite common to find many who fail to use layer functions that would help to speed their work.
The basic operation of a raster program depends on a selected layer. You do not have to build multiple layers, but you do need at least one layer. Pasting an item or creating text in Photoshop automatically creates a new layer. For any other operation, you will have to manually add a layer before drawing. If you do not add a layer, the object will be drawn on the currently selected layer and drawn objects will merge together automatically.
Create a new layer
There are several ways to create a new layer. Select Layer>New>Layer from the Main Menu or use SHIFT+CTRL (Command) + L. I find I most often use the Layers palette for layers operations. With the Layer tab active, click on the side arrow to activate the pop out menu. Click on New Layer. The New Layer window will appear. I advise that you type in a name for your layer, since working with even a few layers will become confusing. Choose a name that you will be able to identify, even if you return to the document months later. Click OK and your new layer will appear immediately above the layer that was selected when you created the new layer.
You can also duplicate a layer, which will copy the selected area and create a new layer to place the copy. Select the layer you wish to copy. Activate the side pop out menu and choose Duplicate Layer. Windows users can also right click on a layer and choose Duplicate Layer from the flyout menu. You will be presented with the Layers Option window, and can rename the copied layer from the Photoshop default, which is the name of the current layer with "copy" added.
When the copy is created, it is placed immediately on top of the original layer, which makes it seem as if nothing has happened. Use the Move tool to move the layer and you will see the new layer as well as the original layer.
Create a layer from a selection
You may wish to copy only a portion of a layer, or perhaps you would prefer that one area of a layer was on its own layer. You can copy or cut any selection to a new layer easily. Activate the layer (click on it) that contains the information you wish to duplicate or move to a new layer and select the area you would like to work with. Choose Layer>New>Layer via Copy or Layer via Cut from the main menu. For a quicker method, right click (Windows) or Command click (Mac) on the layer containing the selected area, and choose the Layer via Copy or Layer via Cut from the flyout menu. The selected area will be duplicated to a new layer if you chose to copy, or moved if you chose the cut option.
I often use the layer via copy or duplicate layer functions when creating navigation elements. Careful naming as you create repeating elements is essential for efficient production.
Rename a layer
If you do not name a layer as you create it, or if you are not presented with the choice to assign a name to a layer, you can easily rename any layer. Double click on the layer in the Layers palette and type a new name into the Name area of the Layer Options window. This window is also available through a right click (Command click) or the side flyout menu.
Change Layer Position
Solid areas in layers will hide the layers below in the stacking order. Quite often, you will find that you need to change the order of the layers. This is a very simple procedure in Photoshop. Simply click and drag the layer to the position you desire. As you are dragging, a clenched hand will appear. Release the mouse when the layer is in the position you require.
Share layers between documents
You can also drag a layer from one Photoshop document to another. Have both documents open – the one containing the layer you wish to copy, and the document that will receive the layer. Click and drag the layer from the original document to the document where you would like to add the layer. The layer will appear in the new document exactly as it was in the original document, but it will also remain in the original location.
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