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