A few more tips to add:
Improving search results: When using Google reverse image search (in Chrome, right-click + Search Google for image), make sure to check the "visually similar images" section. Sometimes you get an image that has been cropped from its original form and this can help identify the original size. If it finds the proper one, run a search on that one and it will yield more results.
Searching for image info (model name, etc.): If the model name doesn't come up in the default search results, click "All sizes" under "Find other sizes of this image." From there, click through each image as the name may be displayed in the information window that appears underneath. This is a quick way of checking without having to load up the whole site (which can sometimes be spammy or otherwise questionable).
Searching for best quality image: This is something I almost always do before posting here. Going back to the "All sizes" page, it will show the resolution specs for each matched image, but be wary of some of the images that look like they have a large resolution-- a lot of the time they're just blown up images of a smaller resolution so it looks like shit when you zoom in. A good way to distinguish these is to open a couple in a new tab by clicking "View Image" and click back and forth between the tabs. You'll see a noticeable difference in quality.
Once in a blue moon when Google is unable to ID the image, I've had luck with https://tineye.com. I very rarely need it, but it's a pretty good image search engine.
Not a fashion model, but she goes by a few names: Toxic A, Angela, or Toksik
Source gallery on MetArt
Edit: added other aliases
Really?? But she used a cropped version of this photo on her Instagram. Let me look into this. Thanks for the heads up.
Edit: Yeah, definitely fake. Original is by David Dubnitskiy who does fucking amazing work. But the real question is why would the official Candice Swanepoel instagram use a fake photo?? LMAO