Here's a pattern I've been playing lately. It really seems to help me focus and center, mentally.
I play this pattern through the circle of fifths, usually with a metronome on.
One practice note: when I'm playing the eighth note version, I strive to keep my slide movement quick and accurate. Another way to look at this: even when playing the eighth notes, I want my slide movements in between the notes to be as quick as if I were playing the fast version.