One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,5,8)(3,7,4,6)(9,10,13,19,14,17,12,18)(11,15,21,16,22,23,20,24)(25,26,30,34)(27,31,37,40)(28,32,29,33)(35,38,36,39)(1,3,5,4)(2,6,8,7)(9,11,12,20,14,22,13,21)(10,15,18,24,17,23,19,16)(25,27)(26,31)(28,36)(29,35)(30,37)(32,39)(33,38)(34,40)(9,11,14,22)(10,16,17,24)(12,21,13,20)(15,18,23,19)(27,35)(28,29)(31,38)(32,33)(36,37)(39,40)(1,4,5,3)(2,7,8,6)(10,17)(15,23)(16,24)(18,19)(25,28,30,29)(26,32,34,33)(27,36,37,35)(31,39,40,38)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.