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