Step 1: Gliding MotionThe most common problem in sweeping will be your picking hand. A lot of people rush this "gliding" motion and almost treat it like a chord strum, or alternatively try to do a lot of consecutive down picks in a row which is impractical and sounds pretty awful. In my video I talk about gently pushing from one string till you're resting on the next. Let's say you're working on a C major arpeggio like the one we see below.
Step 2: Fretting hand and arpeggioThis may seem obvious but it's important you learn your arpeggios inside and out as regularly picked arpeggios before you get the sweep involved. Another important thing when practicing them like this is to do hammer ons and pull offs on strings that have 2 notes in the arpeggio. You'll need to do this when you start sweeping at full speed.
Step 3: Hammer ons and Pull offs in sweepsMost sweeps will have a string that has 2 notes on it. Going back to our C major arpeggio, you'll notice that on the first string we pluck 12 then hammer to 15 then pull off back to 12. You picking hand gliding motion will need to pause before you continue the sweep or your hands will be out of sync. I refer to this in the video as "wasting enough time." Once you get the hang of these pauses you can sweep up an arpeggio, wait for you hammer ons and pull offs to finish then work your way back smoothly.