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