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