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