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