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