Remove any dead flowers that are still hanging on to the plant.
Remove all dead branches using sharp pruners. Cut branches at angles just above the buds.
Cut any suckers growing from the ground around the base of the plant.
Prune branches inside the plant that are rubbing against each other, but avoid main stems. This will promote healthy airflow through the plant, which is especially important for larger plants, as a suffocated interior can invite disease and infestation. Try to cut older or thinner stems rather than newer or thicker stems. If you have a lacecap, mophead or oakleaf hydrangea, keep in mind that buds for upcoming flowers have already formed and any branches with green buds will decrease the plant's flower production.
Shape the plant by trimming the ends of branches just above the first or second bud. Work from the top down.