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