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