Of course, it'd be better if you start showing your baby flash cards as early as possible but 19 months is not too late!!! For saving costs, you can buy some blank cards and write down the words on your own. As for me, I place all the flash cards in a plastic box. I think it'd be better to read the book "How to teach your baby to read" by Glenn Doman beforehand as it'll give a full picture of the whole learning mode.