Present the three sets of primary-color cards to the student. Use a table that has neutral coloring if possible, so there is little to distract him from the bright colors. The cards should be removed from the box and laid randomly on the table. Although they are not in any particular order, they should be straight up and down.
Show the child how to hold the card or tablet correctly by the edges. This is to prevent fading and smearing of the colors over time. Say, "Look how I hold the tablet (or card) so that I do not touch the beautiful color. Can you hold it without touching the color?" This helps preserve the colors on the cards and, in the case of silk-wrapped tablets, helps the silk colors stay bright and smudge-free.
Point to a card and have the child find the card that is the same. Do not use the names of the colors at this time, because the child does not yet know them. If the child selects the right matching card, place the two together side by side, saying, "Yes, these are the same. We will put them together." If the child selects a card that does not match, place the two side by side as if to consider them, then respond, "No, these two are not the same. Find one that is just the same as this one," while pointing to the original request.
Continue to match the colors until all of the colors are placed in pairs on the table. They should be lined up so that one pair is immediately above the other and the matching elements of each color are clear.
Repeat the exercise. If the child is hesitant, you can do the exercise with her again. After she is comfortable with the exercise, allow her to do it on her own. As her familiarity with color grows, you can add additional pairs of colors until the child is working with a complete set of paired colors.