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