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