Today I worked on lessons 2 & 3 on lynda.com Adobe Illustrator CC 2015.
I worked ensuing custom guides. I had to create a new file and made sure to leave a little bleed on the outside. I then went to the view menu and down to rulers, show rulers and then dragged from the ruler edges to create the guides.
I then worked on locking and hiding artwork, used with photos with many layers. You first have to go to the object menu and then select ungroup. You hide all the layers except the one you want to work with by clicking and dragging down your layers panel.
Multi-artboard: I first created a new document and then I went to the art boards panel, where you major your art boards. then you click on the bottom off your art board panel and press new art board. Then you grab the rectangle tool and created a different size of rectangle in each document.