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