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