is the a way of strumming up? like do you only stum a number of strings or the whole chord?

also how do you strum it nicely?
You move the pick upwards in the same motion as you would downwards, self explanitory really.
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You can either strum all of the strings coming back up, or strum the bottom three, or so. Try it various ways and see what sounds best to you.
whatever sounds good at the time
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