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