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