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