Preferences > Site > Dependent files: > Prompt on get/check out (enable)
Then when you Check out the next file, you will be prompted to get dependent file. Answer NO, and enable the "do not ask again" option. Now, whenever you Check Out a new file, you will only get the file, not the images or the CSS or the js that might be needed for proper display of the page in the browser. You can return to the Preferences settings to alter this behavior again.