(also, I could just copy the Install El Capitan in my desktop app folder to the app folder of the laptop..?) Thanks.
Yes, you can. Then, and this is
critical, copy that "install OS X El Capitan" file to another folder/location. In fact, make sure it is on your SD backup/clone, again in another location (I have a folder entitled "OS 10.11 & Upgrades" in a separate location on my SSD, and it of course winds up in the same location on the SD backup/clone). The reason is, once you run "Install OS X El Capitan"
from the Applications Folder, it gets deleted. But, that does not happen running it from anywhere else. (the same will be true for any future OS X (OS 10.12 coming in the fall)).
