Remove any dead branches down to a point of live tissue or down to the crown, at the soil line, if necessary. Make as many cuts as necessary to extricate the entire branch from the shrub mass, as you do not want pieces of the cutting decaying in place.
Inspect the shrub for signs of decaying, diseased or dead foliage and clear away any that you find to make way for new shoots and to safeguard the health of the shrub.
Control the spread of the shrub, within designated boundaries if desired. by trimming back the terminal shoots of the outermost spreading branches. Do this size-control pruning right after the bloom period, each year.
Stimulate new growth in bare areas of the plant by renewal pruning in the defoliated zones, after the bloom cycle. Cut back the bare or sparsely covered branches down to just above a healthy leaf pair or down to the crown. Carefully collect the cuttings and compost or discard them as well.