Always be aware of the giants. You see, the giants are always coming so we must do everything in an effort to accomplish it before they arrive. In case you don't succeed, simply hide under a blanket to avoid them finding you.
This of course is my interpretation of what Graham means when he says, "We better hurry. The giants are coming." He is currently obsessed with monster, giants, and bad guys. He sees them all the time. The dining room has even been full of them at times!