Pick the notes, using your right hand; with the fingers indicated. Pick upwards using the fingertip (Pick downward when using the thumb). You can use the fleshy part of your fingertip or your fingernail; whichever works best for you.
For our next exercise, we will use the same chord, but will use our fingers to pick downwards. Remember to watch the fingering. Start out slowly until your fingers are 'rolling', then pick up speed.
Once you have the technique down, try this exercise. We will use the same fingering as we did in the very first exercise above. Play each staff twice, then move to the next one. Continue to practice it until you are able to play the whole thing in a nice, fluid sounding roll.