G=DihedralGroup(12)
# G is the group of rotational and
# reflectional symmetries of the
# regular 12-sided polygon

HH = [H for H in G.subgroups() if not H.order()==1]
# HH is the set of all subgroups of G

# The following for loop prints the 
# Cayley graph of each subgroup of G
for H in HH:
    show(H.cayley_graph(), vertex_labels=False)