The BEST thing to do is go to the original posters site and read her directions for sizing the pattern. I can tell you right now I didn't agree with the size of her arm holes, I found them too big (or maybe I measured wrong). Either way I'd go there... Here's how I made mine after I had my fabric pieces cut out
Sew sides together, measure on doll and pin to fit.
Sew together. This includes: hem the top, bottom and sleeves closed and add Velcro backing
Are a little trickier. Start by hemming your bottom (this save you time in the long run because you don't have to try to hem in a circle later. Lay out flat (right sides together) and pin top curves only. Sew together. It should look like this:
Now, open it up and take the curve pieces you just sewed on top of each other.
They should look like pant legs now. Pin the bottoms and sew up.
Next if your doll is handy I recommend trying it on the doll and making them fit perfectly. Sew top closed, except for a small hole- you'll need it to fit the elastic through.
I wrapped a piece around the dolls waist and cut to fit. Then slid the elastic through the top hem we just made and sewed it closed.
Cut a square 3 inches by 5 inches. Fold in half and sew up. Turn right side out and add ribbon to top and bottom. Sew together.
Now that your doll is a doctor, she could use an cast to put on her patients!
How about some crutches and leg cast?