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