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