Good soil makes gardening easy, as plants grow strong in it and achieve their personal best.
To improve the soil in an established garden, you can simply shred the leaves that accumulate from the trees in your yard and spread them about 6” deep over the garden beds. This is the classic method of sheet composting, and straw (without grass seeds) and seaweed can also be used to enhance the soil this way.
In the spring you will notice that the vegetative matter will have decomposed into humus that is rich in beneficial organisms. The soil structure is helped because humus encourages fungi, bacteria and earthworms, which make the soil porous, allowing both air and water to penetrate more freely.
If you wish to create a new garden bed, outline the shape you prefer with a garden hose before you begin. Then lay down organic matter such as leaves, plus layers of newspaper and cardboard, water well, and then apply more leaves or vegetative matter. Next spring you can plant directly through the layers.
Be careful to keep compost and mulch away from the trunks of existing trees and shrubs though, as critters will hunker down in it to keep warm and will chew on your plantings.