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