Potting and Repotting
The best way to learn is to practice. Start with an inexpensive 1 gallon nursery plant (such as a juniper).
Have everything at hand. Work away from direct sun and out of any wind, both of which tend to dry out exposed roots. If you plan on repotting a nursery plant immediately, have the nurseryman cut the can. Otherwise, leave it uncut, since roots will dry out quickly.
Have your tools and materials handy: pruning shears, couple of chopsticks, bucket half full of water, your new container, with a piece of broken pottery over the drain hole, and about a third of soil mix; extra soil mix to fill container once plant is in, sprinkling can with spray nozzle, moss, rocks or whatever you plan to use around the base of the plant.
Inspect the root ball carefully. If you see only a few roots on the side and bottom of the ball, treat it gently. If the ball is webbed, treat it boldly, since there are probably more roots than soil. If there are large roots circling the ball, unwind them first and snip them off entirely! Otherwise they will eventually cripple the tree.