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