Get the top you want to take the sleeves off, maybe because the sleeves are to short but you still like the design.

Turn it inside out.

Find the seam that joins the sleeves.

Ruffly cut off the sleve

cut right along next to the seam but DO NOT actually cut the seam!!!
Then pull it to make any unneat bits curl under.

Do the same for the other sleeve

Then you are all done!!!!!