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