Make a list of the vocabulary words you want to use. This list should be large enough that you can make three completely different cards (i.e., no repeating words) of at least 12 letters apiece; you'll make more than three, but the actual cards you make will have repeating words.
Figure out how to fit the words you want on a grid. Decide how many words you want on each card; this number should be a multiple and not a prime. Create the grid based on finding the combination of multiplied numbers that are closest to one another and basing the number of rows and columns off this. For example, if you have 12 vocabulary words, plan to make four rows of three rather than two rows of six. As you figure your numbers, consider whether or not you want to add a "free" space in addition to the vocab words you've selected.
Write all the vocab words on separate scraps of paper. Draw these out of a hat to determine the selection of words for each card you make.
Sketch out the grid for a card on a large piece of tag board. Make each section of the card about three inches square.
Draw the dots for the Braille in marker.
Cover each marker dot with a dot of glue. Pour some school glue onto a paper plate and insert a toothpick into the glue, coating the tip. Press the toothpick to each dot, then repeat with a fresh application of glue for the next dot. Start in the upper left-hand corner of each cord and work your way right and down, ensuring that your arm will be less likely to drag through the work you've already done.
Let the glue dry, then check on the Braille dots. If any of them seem too flat, apply a second blob of glue.
Repeat steps three to seven for each card you want to make.