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