Begin visual inspection at the top of the tree and work downward.
Use The ⅓ and ¼ Rules of Pruning
Never remove more than ¼ of a tree’s crown in a season
Ideally, main side branches should be at least ⅓ smaller than the diameter of the trunk.
For most deciduous (broadleaf) trees, don’t prune up from the bottom any more than ⅓ of the tree’s total height.
Where possible, try to encourage side branches that form angles that are ⅓ off vertical that form “10 o’clock” or “2 o’clock” angles with the trunk.
For most species, the tree should have a single trunk. Identify the best leader and later branches before you begin pruning and remove defective parts before pruning for form.
Don’t worry about protecting pruning cuts. For aesthetics, you may feel better painting large wounds but it doesn’t prevent or reduce decay.
Keep tools sharp. One-hand pruning shears with curved blades work best on young trees.
For high branches use a pole pruner. A major job on a big tree should be done by a professional arborist.
For larger branches, cut outside the branch bark and ridge collar (swollen area). Do not leave a protruding stub. If the limb is too small to have formed a collar cut close.