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