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