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