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