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