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