DIY Racerback Tank

Any normal tshirt

cut off the neckline border all around

cut off the sleeves

fold the shirt in half and place the first cut off sleeve as a template and cut the second one

cut off the bottom hemming of the shirt

you'll be left with this stringy-thingy but DON'T THROW IT AWAY! we'll need it later on

cut the sleeves on the BACK SIDE ONLY a little deeper 

cut a deep v-shape in the back of the neck line 

take the string i told you to keep and double knot the back sleeves together two inches above the v-neck you just cut

keep tying it around until you get to the end of the string and double knot it again

all done!