Danny Korem shares a few tips about making selections in AutoCAD.
"If I make systematic work my habit, I can isolate a layer (either by turning other layers off or locking them), then choose Select All, and perform a Properties Modification/Change. This will affect only objects residing in unlocked layers.
"Another method is all about named views. When I create a named view, I usually leave the default 'Save layer snapshot with view.' Then when I restore the named view, I can see fewer objects than usual, making the selection set easier to create."
Notes from Brian Benton, Cadalyst tip reviewer: Objects on locked layers cannot be edited. One way to clear up your selection set possible targets is to lock layers.
This is a very good idea when dealing with an xref. Put your xref on a specific layer and lock the layer. You won’t be able to accidently delete the xref (or block, or text, or title block). If you don’t use saved views, you should consider it. There are a lot of uses for them.
Saving a certain layer state for your view is a great way to isolate specific linework under specific layer conditions. If there is an area that you will need frequent access to for editing, consider creating a saved name view for it. You can also add saved views to your sheet set, giving you quick and easy access to those lines.