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