At a bike shop where I worked in high school. Definitely need a truing stand, and the right spoke wrench for whatever spokes you're using. Remember that as you tighten and loosen spokes to correct left and right wobbles, you're also pulling or pushing the the wheel out-of-round. What's frustrating is when you finally get it perfect, you need to take it out of the stand, put it sideways on the ground (resting on the hub), and then push and pull the rim at different points to relieve the stresses you just put into the spokes/nipples, and then start all over again because this process puts it back out of true. Do this several times. But each iteration gets closer to being "final". These last step are what a lot of shops don't do so it looks true when you take it home but goes untrue quickly.