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