Uses strict up down or down up picking strokes when playing scales and solos. A rule of thumb is: when picking from low to high strings, start with a downstroke (and alternate). When picking from high to low strings, start with an upstroke (and alternate. This technique makes for very precise guitar playing and is the first picking technique a guitar student should master, before moving on to other forms of picking.
If you want to improve your sloppy, inaccurate and slow playing, work on Alternate Picking. A lot of my students want to improve their articulation and the first thing I check is their alternate picking style.
I have written a nice shred guitar speed exercise that employes alternate picking. You can find it on my blog site at: Shred Guitar Speed Exercise using Alternate Picking