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