saving files to storage

Open Finder in your Dock. Then right click on the ext. Drive and open it in a new window. To move a file either right click it and "Copy". Then Paste it by right clicking in the ext. Drive window, Or, simply drag and drop the file from one window to the other. When you get a new machine you can transfer the files the same way.

You could use a USB drive, an external HD or SSB, or burn them to a disk if you have a DVD-RW disk player.