The essentials.
The first thing you should decide when considering growing Bonsai Trees is what type of tree you want to grow. The type of tree you want will determine not only the tree you should buy but also the design of pot and the types of tools you may require, and of course you should have the knowledge of growing the particular type of Bonsai tree that you want. Not all Bonsai trees demand the same attention. For instance draping trees will need very different pruning to a conifer and so you should have the knowledge to grow exactly what type of tree you want.
After this, it's time to prepare yourself; you will need the appropriate tools and one good pot at the very least.
Tools.
The tools you will need include various sizes of wire and wire cutters, a small and large pair of scissors, a small pair of sharp garden shears and larger pair of pruners to cut through the thick branches.
Bonsai or not Bonsai?
Many places now sell Bonsai that are ready trained and have grown into healthy but juvenile Bonsai. As long as you are careful to pick a healthy and good looking tree then care, attention and an eye for detail means you will be able to buy a partially grown Bonsai and help it grow into a perfect full blown Bonsai. However, should you decide to buy a full grown tree or plant, then it is a good idea to visit the nurseries that stock trained Bonsai. This way you can get an idea for what type of tree you want and how they should look. It can be very difficult to see past the shape the tree already has, but remember when you want to train a tree to become your Bonsai project you will be cutting most of the branches and foliage away so it will look very dissimilar to how you first see it. You need to have good vision for this method.
Planting.
You can buy a Bonsai pot from virtually any plant shop, but make sure it has adequate drainage and preferably has little feet on it to allow the water to drain away and also allow a good level of airflow. Using a soil consisting of half organic matter and half grit will allow a good level of drainage while still giving the plant the anchorage it will need in it's shallow pot.
Now cover the drainage holes in the bottom of your pot with a wire screen in order to prevent the soil running out. Now place a layer of grit down followed by the Bonsai soil. Now you should shape your Bonsai how you want it. Place the wire around the branches in a spiral shape, and gently bend the branches to the exact shape you want them to grow in. Be careful, though, not to break or snap any of the branches you shape. Next remove as much of the soil from the root ball as you can but be sure to leave as many of the fine feeder roots as possible and then plant your Bonsai into the pot you have prepared.