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