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)(16,23)(19,24)(21,22)(25,26,32,30)(27,36,38,33)(28,39,34,29)(31,35,40,37)(1,3)(2,6)(4,7)(5,8)(9,10)(11,15)(12,16)(13,17)(14,18)(19,22)(20,23)(21,24)(25,27,32,38)(26,33,30,36)(28,31,34,40)(29,35,39,37)(9,11)(10,13)(12,19)(14,17)(15,18)(16,21)(20,24)(22,23)(25,28)(26,29)(27,31)(30,39)(32,34)(33,35)(36,37)(38,40) involution — undirected(2,7)(4,6)(9,11)(10,15)(12,19)(13,18)(14,17)(16,22)(20,24)(21,23)(25,29,32,39)(26,34,30,28)(27,37,38,35)(31,36,40,33)(1,3)(2,6)(4,7)(5,8)(9,12,14,20)(10,16,18,23)(11,19,17,24)(13,21,15,22)(25,30,32,26)(27,36,38,33)(28,39,34,29)(31,37,40,35)(1,4,5,6)(2,3,7,8)(9,13,14,15)(10,17,18,11)(12,21,20,22)(16,24,23,19)(25,31,32,40)(26,35,30,37)(27,34,38,28)(29,33,39,36)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.