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