Select appropriate species for the site. Different species of trees will require different amounts of moisture, sunlight, soil nutrients and space. Selecting a tree that matches your chosen location means less maintenance in the future.
For safety locate underground utilities before digging. If the species you have selected grows tall you may need to consider overhead utilities as well.
Determine proper depth. Trees planted too deeply in the soil is a common problem. This can result in slow growth, decay, increased susceptibility to pests and disease. If you observe trees growing naturally in the forest you can see the buttress roots forming a flare at the base of the trunk where it meets the soil. If the trunk of your new tree is cylindrical like a pole all the way down to the soil line then the roots are too deep. You may need to remove some soil from the top of the root ball. The tree pictured is planted at the correct depth, there is a visible flare at the base of the trunk.
Give the roots a chance to grow. Dig a generous size hole for the root ball. If the soil is hard and compact, which is common on homesites, loosen soil at the perimeter of the hole to make it easier for the roots to expand. If the tree roots are wrapped in burlap, remove as much of the burlap, twin and wire as possible before filling the hole. Twine and wire can strangle the tree as it grows.
Fill the planting hole gently but firmly. Water thoroughly to ensure that soil settles in around the roots. A thin layer of mulch is beneficial, too much can cause the same problems as planting too deep. The mulch should not touch the trunk of the tree. Keep the depth less than two inches.
Your new tree will take time to establish itself in its new home. Monitor the tree for signs of stress. Keep it watered as appropriate for the species you have selected. The larger the tree you transplant, the longer it will take to recover.