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