Best way to mark cards with an invisible luminous pen

 Since marked playing cards are popular use in poker games nowadays, many people are curious about how to mark playing cards themselves.

The invisible ink or the invisible luminous pen is always the choice for marking poker cards. How to mark cards with an invisible luminous pen well for contact lenses?
Firstly, you need to get the right ink or invisible luminous pen.
Secondly, try marking the back of the playing cards lightly with the same color ink. Usually the pen of red invisible ink can be suitable to the red cards only.
Thirdly, clean the visible marks on the cards back carefully and then leave the invisible marks there.
Lastly, you need to get a good pair of luminous ink glasses or infrared contact lenses so as to read the luminous marks on the marking cards.