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