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)(13,14,19,18)(15,20,17,22)(16,21,26,28)(23,25,27,24)(6,9)(10,12)(13,15,19,17)(14,20,18,22)(16,24,26,25)(21,23,28,27)(2,4)(13,16,19,26)(14,21,18,28)(15,23,17,27)(20,25,22,24)(5,7,8,11)(6,10,9,12)(13,17,19,15)(14,22,18,20)(16,25,26,24)(21,27,28,23)(14,18)(15,22)(16,26)(17,20)(23,25)(24,27) 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.