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