A microwave-compatible lithography-free process is shown to allow the electrical contact of a single nanometric spin valve grown by template synthesis. The complex spin dynamics of a single nanomagnet is revealed by resonant microwave current excitations, detected electrically in the V-dc and second-harmonic voltages. The uniform modes are attributed to spin transfer torque effects, whereas the effect of oersted field may play a role in exciting the nonuniform modes.