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