A more detailed explanation is given using the diagram below.
Without slots in the metal, circular eddy currents are easily formed, as shown in the diagram below.
The metal sheet is swinging to the right and has just entered the magnetic field. A clockwise, circular eddy current is induced in the copper sheet to resist this motion.
The metal sheet is still swinging to the right and is half way out of the magnetic field. An anti-clockwise, circular eddy current is induced in the copper sheet to resist this motion.
If you use the right hand solenoid rule or the right hand motor rule you should arrive at the same direction of the induced current.
To look at some eddy currents in action, follow the link below:
Properties of eddy currents.