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