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