Watch the Connecting Pentatonics Exercise 1 online guitar lesson by Jeff McErlain from Beginner Blues-Rock Soloing
After you've learned this fingering in the key of D minor as shown, move to a different key and learn it there. I highly recommend moving to the key of A minor next and E minor after that. These are two of the most popular guitar keys that will get quite a bit of use.
As demonstrated, play them with the metronome nice and slowly and deliberately. Slowly move up the tempo of the metronome and see how far you can take it before we start to get sloppy.