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