You can if you like, it's totally up to you. I prefer to show pictures/videos because it teaches the meaning of the words along with the "how" of reading. When Glenn Doman wrote his book, there was no Little Reader and technology to help us deliver flashcards. If you have not done so already, I highly recommend downloading the free two week trial of Little Reader. Making flash cards by hand gets OLD!
So it;s nice to have the curriculum pre-made for you, and if you like to use paper flashcards because it's your preference, you can still print them out and show them the old fashioned way. Best of luck!