In addition to the use of publishing by modifying your org-publish-project-alist
variable as @user1248256 suggested, you can directly specify the org-export-publishing-directory
variable within your file:
#+bind: org-export-publishing-directory "./exports"
* This is a test headline
Some text here. This should be exported to the "./exports" directory.
Upon export it will be placed in the “exports” directory, but only if that directory exists. If it does not exist, you will get an error message in the console.