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