In this quote its Ralph pacing back and forth on the sand. ralph is doing this so he can think and it is one of the only places on the island where he can not watch his feet. We can assume he is always watching his feet so he does not step on a snake or in quicksand. The quote talks about him always trying to improvise. He has to do that because everyone is looking up to him and that is a lot of pressure and with everyone asking you questions all the time you have to improvise or you would spend all your time answering questions. This is why h is so tired because when he is not answering people he is always building or fixing things. This is the only time that he can forget about looking down and improvising and actually think and answer the problem at hand. This is important because he realizes how trying this job really is and how he always has to look at his feet in a figurative way. I think that the figurative way is him always looking down at his feet so he does not make and mistake that can effect the entire group.