Using dwarf apple trees as an example, you will likely use what is termed the central leader system to train your trees. The central leader system allows your fruit tree to look much more like most other trees in your landscape, yet produce apples without the tree looking like those you see in older commercial orchards. Training starts the first year you plant your fruit trees. This keeps your fruit tree ensuring your dwarf tree actually remains dwarf in your home orchard. You will be able to start to select your scaffold branches placing the first set of scaffold branches no more than 20 -24 inches from the ground. By starting that low, you will be able to place additional scaffolds and still have a mature tree that is no taller than 6 to 8 feet tall, making it very easy to manage.
There are several other advantages of a well-trained dwarf fruit tree. Annual spring pruning will be visually much clearer as to which branches need your attention. There will be branches that need to be adjusted using traditional branch spreaders or alternative methods such as using twine and a stake to pull the branch into the desired horizontal plane as you develop your scaffolds. Water sprouts will be easily identified, as they will be growing straight up from the horizontal scaffold branches.
As your dwarf fruit tree matures in size, home orchardists will realize there are additional benefits. The weekly inspection and monitoring of fruit pests will be easier and done very quickly. Even though young fruit tree may not be producing apples, there are insects and foliar diseases that need to be taken care of. Foliage feeding insects reduce the canopy, reducing the amount of food that could go into growth and development. Leaf diseases have a similar impact. If allowed to continue over the season or seasons, it could easily delay fruit production and in a bigger picture, lesson the overall vigor. You want a tree that develops quickly, so that your training then can encourage flowers and fruit set. Limited fruits can begin to show up as early as the third year and get more productive every year after. Enjoy the challenge and amaze your friends with fruit that came right out of your yard.