To change the visibility of a layer, click the layer icon, or click a layer name with the
to display a pull-down menu of layer operations (such as Visible, Symmetry, Assign, Insert New Layer, and so on), and choose Visible.
To make the current layer visible and all other siblings invisible, Alt-click the visibility icon next to the layer name.
To make all layers visible or invisible, Shift-click the visibility icon next to the layer name.
To change a layer color, hold the
on the layer icon or click with the
on a layer color swatch to open the layer color palette.

To display both the layer names and numbers (or only numbers), open the Preferences > General Preferences option window. Choose Modeling from the list on the left and set Modeling layers mode to Both (or Number for numbers only).
Only the layer name is editable (by double-clicking on it).
Click an object (curve, surface, and so on) with the
to display a pull-down menu containing the following choices:
In Layer mode, you can re-order layers or move objects between layers by using the
to drag and drop.
In the same manner, you can also drag and drop a layer from the Object Lister into a category in the Layer Categories editor (Windows > Information > Layer Categories).