A quick tip, take a zip tie, attach it around either your seat stay or chainstay. Cut it to where it barely rubs the rim, use that as your guide. When removing the wheel, just turn the zip tie out of the way. It's a cheap tool tip for "on the bike" wheel truing!
L8R
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"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "WOW, What a Ride!" - unknown
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