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