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