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