If you are covering a cake in sugar crystals and/or fairy dust (those sparkly sugar flakes), how do you get it on the sides. Is there a special technique, or ???? they just kind of fall off the edge and you get a few on the sides. any nifty tricks to this?

You have to put it on fresh b'cream or fondant.
Tilt the cake & sprinkle away.
OR use a soft paint brush.