One thing that I can't stress enough is, WHERE you get your bird. If you're going for the hand raised baby bird route, make sure you choose a breeder who will socialize his babies to various people/situations, fledge the babies before choosing to clip, and offer a wide range of foods from an early age. Ask if he'd be willing to start on the harness training as well, a good breeder should be willing to.
I personally don't like pet stores, except for the few specialty bird stores that do a good job. But almost every bird store I've seen/seen videos of/heard of, big red flags for me. They look like factories that pump out birds rather than a healthy environment for growing babies.
Rescue/Sanctuary/Craigslist/Kijiji is a good way too. Many baby birds change in personality and in their choosing of a favourite person as they hit maturity; just like human babies that are drastically different from adult humans, a baby bird can grow to be an adult that may be completely opposite of its baby stage. With an older bird, you see what you get. No crazy hormonal/personality changes to deal with. Prices are usually cheaper too.
One thing that I want to stress for when you do get your bird is to give it lots of enrichment. Foraging is the biggest enrichment for captive and wild birds, and you can buy many cool types of foraging toys online for bits of treats/toys/meal portions. This is a good Do-It-Yourself foraging webiste.
http://foragingforparrots.com/