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