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