Separate your white fondant into six equal portions, reserving one portion to remain uncoloured. Using a small conversation heart as a basis of comparison, gently knead the remaining five colours into your pretty pastels. (You'll want to blend the two colours listed above for yellow and green.) Once colour is fully incorporated, roll the fondant into a ball and cover it tightly with plastic wrap. Store in a cool, dry place.
Note: This step should be done the day before to save time.