Here are a couple of links with great tutorials on making these for your babies. Some of my friends tried making the cards and also the picture detail checker board (last link). For the cards, the paper weight matter so getting thicker papers may be helpful.
http://domanmom.com/2015/08/word-cards/
http://www.mummyshomeschool.com/shichida-flashcards-how-to-make/
grhomeschooling.blogspot.com/2011/07/tutorial-how-to-make-picture-detail.html
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