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