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