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