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