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