In Windows, create a folder called curl in your C: drive.
Go to http://curl.haxx.se/download.html and download one of the following zip files:
Unzip the downloaded file and move the curl.exe file to your C:\curl folder.
The curl.exe file will be located in the C:\Curl\bin directory.
Add C:\Curl\bin to your PATH environment variable so that Windows can find curl.exe without specifying the full path.