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