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