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