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