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