One vertex per element, one color per generator, with an edge from x to x·s.
(3,7)(5,8)(9,10,14,18)(11,13,17,15)(12,16,20,24)(19,22,21,23)(25,26)(27,32)(28,29)(30,34)(31,35)(33,40)(36,39)(37,38)(1,2,4,6)(3,5,7,8)(9,10)(11,15)(12,16)(13,17)(14,18)(19,23)(20,24)(21,22)(27,35)(31,32)(36,38)(37,39)(1,3)(2,5)(4,7)(6,8)(11,17)(12,20)(13,15)(16,24)(25,27,30,35)(26,31,34,32)(28,38,33,36)(29,39,40,37)(9,11,14,17)(10,15,18,13)(12,21,20,19)(16,22,24,23)(25,28,30,33)(26,29,34,40)(27,36,35,38)(31,37,32,39)(1,2)(3,5)(4,6)(7,8)(9,12,14,20)(10,16,18,24)(11,19,17,21)(13,22,15,23)(25,27)(26,32)(28,38)(29,37)(30,35)(31,34)(33,36)(39,40)(1,3)(2,5)(4,7)(6,8)(9,13,14,15)(10,17,18,11)(12,22,20,23)(16,21,24,19)(25,29)(26,33)(27,37)(28,34)(30,40)(31,38)(32,36)(35,39)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.