There are 2 ways of making a Sticky Note on your Mac.  The first way of creating a new note as easy as highlighting the text and/or images you want to jot down and pressing a keyboard shortcut. That shortcut? Command-Shift-Y.  Your new note will near-instantly appear on your screen, containing the text you just had selected.

If keyboard shortcuts aren’t your preference, there is a second approach, too. You still start by highlighting whatever it is you’d like to save in Sticky form. In this method, however, you simply drag your selection onto the Stickies icon in your Dock. Once again, your newly-created note will leap to the front of your screen, reflecting the entirety of your selection.