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