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