Sewing My Cape is Constantly Flowing!

You could try tailoring it to fit around the shoulders and sew in some darts and pleats - it won't result in a flowy cape, though, if this is what you are after, but at least it won't float around like this. Google for fitted cape patterns and you should find some options of how to construct such a garment with less drapey materials.

 

Does wiring work at 1/4? It's a crummy solution but it's a solution for smaller scales.

 

Thinner fabric would definitely help in your future cape-making. Also, it looks like the lining fabric might be the same type of fabric as the outer cape? In which case using dedicated lining fabric (thin and silky) will help as well.

 

This is a terrible drawing but you could add darts to the red areas (at least middle back and shoulders) to make the lower hem less wide and bit of a better fit easily if you still want to fiddle around with the current garment. You can later use the improved measurements to make a new pattern from your work. Sometimes doll clothes just need less fabric to counteract with the thickness of materials and the small scale of the body

Spoiler

 

This.

Fabric weight/thickness needs to be scaled down more the smaller the doll you are sewing for is. The cape in the picture looks like you used a fairly substantial fabric for both the outer and the lining. whihc means that double thickness is doubled again around a the hem making it even stiffer/bulkier right at the point where you want it to be most drapey and flexible

In addition to getting a thinner, more drapey fabric for the outer layer, I'd suggest getting something ultra thin for any linings you do in doll scale - the finer the better as on more fitted garments a heavy lining will add unwanted bulk to the doll's figure. I tend to default to a thin cotton lawn for linings (or even lighter, if I can get it).

As for taming the existing cape, cutting it down to a more fitted shape around the shoulders and down the sides would probably be the best option. Something along the lines of the shapes shown here: https://sewguide.com/wp-content/uploads/2018/09/cape.png

Teddy

 

That's a nice idea! Fishing sinkers perhaps?

 

For a drapy cloak, use a light-weight woven fabric with a floaty, drapy hand, like lawn cotton or a lightweight silk maybe (something between 8 to 16 momme), line with an equally lightweight fabric, and cut all pattern pieces on the bias for that extra bit of drape! Think floaty silk scarf material. I often find cheap silk scarves in consignment or goodwill type shops!