Don't create a flower bed around an unsightly feature such as a fire hydrant. It only draws more attention to that feature.
Store watering can upside down after use to help prevent rust.
Avoid, if possible, installed and maintaining a bed where you must haul in water. A hot, dry summer can defeat you.
Use trees and shrubs that have more than one feature or seasonal interest.
Let foliage from spring bulbs stay in place after the flower dies. Leaves make food reserves for next year's blossoms.
Plants watered too often will develop shallow roots and will lose their tolerance for drought.
Don't leave sprinklers running so long that water forms puddles. Beneficial microorganisms drown in saturated soil. Also, plants gasp for oxygen and stop absorbing nutrients. Plants need about 1" per week during growing season.
Prune trees and shrubs to avoid interfering with homes, fences, etc..., improve wind resistance, gain access to fruit and to create good branching structure.