The original tee shirt is pretty sad looking, stretched out of shape and a bit faded under the arms.
I cut the tee up cutting down all the original seams so the front, back and sleeves are all separate
I've left a bit of extra length in the sleeves to try and avoid the faded patches under the arms, and used the original double sleeve ends, I'll do the same with the front and back to keep the look.
Next, sew the shoulder seams together
Sew the neckband seam, fold in half and place pins in the four quarters
Divide the neck into four and pin the neckband on
Sew the neckband on, you should get something looking like this
Next sew up the side and arm seams, because I'm using the original cuffs there is nothing else to do but zigzag over the loose overlocker ends to finish
The finished tee, a bit on the large side but a vast improvement on the saggy baggy original!