Tile 48 times to learn how to tile two more times. That should be enough information - or maybe even a bit extra?

Hint 2

How might you find the intersection of two complete coverings? Keep in mind each covering uses exactly one of each type of piece.
Don't try anagramming after you've had one too many.

Hint 3

If a red and blue tile of the same shape overlap, take the overlapped area's corresponding letters - assuming the alphabet assignment loops after Z.
Your resulting letters will almost anagram to give a word, but one letter needs to be cut out... what could these 12 blue-framed and 12 red-framed extra triangle pieces be for?