A few nights ago, I altered the 7 tank tops I have had for a few years. They're nothing special. I only wear them around the apartment -- or out if it's over 90 degrees. I didn't mind that they were loose (2 sizes too large, now) but because they were so loose, the arm holes, which were generous became gigantic and far too exposing.
Tuesday evening, I took them up at the shoulders. Nothing too tricky, except the width of the straps on the front differed from the back so I had to stretch the narrower strap to match the wider one, so the shoulder join didn't look crummy.
Although I use polyester thread in most of my sewing projects, other than piecing cotton fabric, I used cotton on these because I usually throw them into a hot dryer after they are washed. For these, the little bit of temporary shrinkage is a plus.
One more small sewing chore is ticked off my To Sew list. Yay!