Sleeves are awesome. I am gonna show you how to make sleeves which are awesome.
1. Measure your doll starting from the wrist, then up the arm, then across the chest, then back down the other arm. (Mine was about 14")
2. Measure around the top of the arm. (Mine was about 5-6")
3. Crochet a rectangle that is 14"* wide and 5-6"* tall.
4. Place your doll on the crochet rectangle and start to wrap the crochet rectangle ends around the arms. Measure the space of the body. (Mine was about 5")
5. Fold it in half (The good side inside) and measure 5"* in the middle of the rectangle
6. Stitch the sleeves together. (The part that's not the middle space for the body)
7. Once done stitching both sides, flip it inside-out and you have awesomeness.
*Or however long your doll is.
Hope it wasn't too confusing!