Place a toothpick in the crack to open it up so you can insert glue.
Spread a little wax around the crack on the top of the table to protect the surface from excess glue that may ooze out of the crack. Be careful not to get any wax in the crack itself.
Squeeze a small amount of glue into the crack. Move the toothpick back and forth so the glue can flow all the way through the crack. Stop applying glue when the crack is completely filled.
Remove the toothpick and apply pressure to the side of the table to hold the crack closed until the glue dries. This will only take a few minutes.
Wipe away the wax from the top of the table.