Things You'll Need
Instructions
Hold the cube with one side facing you. It doesn't matter which side.
Rotate the top layer of the cube 45 degrees, so that one of the corners of the top layer is pointing at you. (When you look at the cube from the top, it should look like an eight-pointed star.)
Set the cube down on a flat surface.
Gently work the flat handle of a fork or spoon under one of the "edge" pieces on the top layer. Each layer consists of nine pieces: a center piece, which has only one visible side; four corner pieces, each of which has three visible sides; and four edge pieces, each of which has two visible sides. It's one of these two-sided pieces you want to remove.
Pry the edge piece out gently. Try to wiggle the piece out, rather than applying brute force, which could snap the plastic stem that holds the piece in place.
Spray a little silicone oil into the open space left by the missing piece, making sure to get it onto the center assembly. A brief squirt should be all you need.
Place the missing edge piece back in position. Insert it at an angle, so the stem fits under the center piece. Apply gentle pressure downward to pop the piece in place. Wipe off any silicone oil that may have gotten on the outside of the cube.
"Work" the cube for a while. Turn each of the sides a dozen or so times to distribute the oil. If it's still a little sticky, repeat the process.