Always wash the cutting blades of secateurs, loppers and saws in diluted garden disinfectant after use, particularly when diseased wood is cut. This is to prevent the spread of diseases from plant to plant.
When pruning healthy wood, make an angled cut using bypass secateurs. Cut close to a healthy bud, sloping away from it.
If you're not sure when a climber or wall shrub is best pruned, a useful guide is to prune spring and early summer-flowering plants when their blooms fade. Those flowering in late summer usually do so on the current year's growth, so encourage this by pruning in late winter.