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