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