Senior Engineering Designer Perry Medina noticed this shortcut that can save time when you're changing the assigned color, linetype, or lineweight of several layers to the same common property in the layer properties palette.
"Here's how it would work for assigning a similar linetype to layers with different linetypes. Select the desired layers. If one of your layers already has the linetype you want to use, select it also. Click on the layer that already has the linetype you want to change the others to, and it will show up in the dialog box as the default linetype to use. So now you can press Enter or click OK, and all the layers selected have that linetype without you having to select it and browse the list of available linetypes. This also works with layer colors and lineweights."
Notes from Cadalyst Tip Patrol: One key to increasing efficiency in AutoCAD is to reduce your work: eliminate picks, clicks, and entries whenever possible; move your mouse less; use both hands; etc. There will be many times when you need several layers to look the same, and using this method can help you change many layers at once.