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