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