|When and how should pruning be done?|
|Yours is a pretty general question so it's hard to give specifics for the plants in your landscape. However, most pruning is done in the early spring, just as new growth begins. Exceptions to this are shrubs and trees that bloom in spring. Those should be pruned immediately after flowering has finished. Fruit trees are typically pruned in winter; roses in December in your gardening region. How much or little to prune really depends upon the types of plants you're pruning. If you submit another question identifying the plants you want to prune we can provide specifics to those plants.
Best wishes with your landscape!