Start with the lessons, then move into Syn’s Etudes on sweeping. Take them REALLY SLOW. I’ve been playing 35 years and never really did sweeping PROPERLY. I’ve been working on Etude #1 for a couple of months to make sure I’m getting everything as clean and right as I can.
Now, I say a couple of months, but I only spend about 5 minutes a day, 5-6 days a week on that specifically. Your mileage may vary, but the point is, to do it RIGHT takes a SERIOUSLY long time.