When I practice moving up a scale, I'm sloppy when moving from string to string. For example, as I move up a scale and change to the next string, the string I'm leaving makes a sound.

This happens to me either playing slow or fast. When I'm going down a scale, I don't have this issue.

What suggestions or techniques do you have to move from string to string "quietly"?

slightly "damp" the string you're leaving either with your picking hand palm or a finger on your fretting hand.
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