A bird should be able to fly through a tree;
it should NOT be a dense wall.
Use you anvil pruners for those herbaceous plants less than the
thickness of a pencil.
Use your by-pass pruners for woody plants.
When pruning roses or diseased plants, disinfect your clippers
with rubbing alcohol, 10 water:1 bleach, or Lysol disinfectant spray
to discourage the spread of disease.
Always be sure to leave a bit of the stub end of pruned wood so
that you have made the smallest possible cut which can then form a
callous.
Best time to prune is when plants are dormant (Nov-March); worst
time: August-Oct. If spring bloomers do not need a major overhaul,
prune after bloom.