Introduction: Rubik's Cube 3x3 Dot in Center
Make sure the Rubik's Cube is solved.
Now pick 2 sides of the cube and remember them.
When you have your 2 sides turn L and R 90 degrees.
Then turn U and Bo 90 degrees
Now, you turn the F and Ba sides 90 degrees
Last, you turn L and R 90 degrees again.
Congrats you made a dot in the center of each side. To get the cube back to normal, do the steps 2 more times. Use the same side I told you to remember.