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