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