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