taimatsu no monogatari

Sleeves are a pain to do right, they're deceptively shaped.

You *roughly* want a shape like this:

         TOP (ie folded)
      --------------.
      z              |
      z              |
      z             /
      z           /
      z         /
      z        /
      z       |
      z       |
      --------
  BOTTOM (ie seam)

(z = cutoff from diagram, no need to draw whole length of sleeve!)

with the total length of the seams obviously corresponding to the

       ---------------
       \
        \
         \
          |
          |
          |
          |
          |
          |
         /
        /
       /
      /
      |
      | 

curve of the 'armhole'.

Find an existing top you have and mock out with paper/scraps to see how it goes together - the widest part of the curve fits over the shoulder, the narrowest draws in for the underarm.

IN fact, if you have a similar cut top of similar fabric, you should be able to use it as a pattern properly...

(let's see if this formats right)