Finding the “perfect curve” was elusive for me. Actually to be more precise, it was (at first) due to a lack of $$$.
I started with the underworks underwear/padding. Wasn’t great but for the budget concious it works in a pinch. The padding that comes with it is very thin, so I made my own. However, because of the extra weight I got the dreaded hip droop as the underwear wouldn’t stay up that well due to the extra weight.
I tried panties with silicone inserts, same deal it didn’t give me the curves I wanted.
I finally ponied up the $$$ for the dresstech silicone hip pads. I bought the normal size and it was like night and day. At that time, I bought some cheaper silicone butt pads from aliexpress, and it did the job.
Fast forward a year later, and I bought a 2nd pair of dresstech hip pads, large girl. I also splurged and bought their silicone butt pads. This was the elusive curve I was looking for. Wearing tight skirts you can really see the curves shine thru. Like someone mentioned, these silicone pads are secured in place by shapewear, and I’m a big fan of shapewear so that is another bonus.