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