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