STEP 1: Open the webpage containing the form in your web browser. Now right click (preferably on the form) and press Inspect Element option to open the Developer Tools. (OR) Click on the hamburger icon in your browser at the top right corner and select More Tools -> Developer Tools.
Locating "Developer Mode"
STEP 2: Now press CTRL + F to open find widget inside the elements tab of the Developer Tools. Typing Form highlights all the form tags present on the webpage.
Finding "form" on your webpage
In the above image, Form highlighted has the ID as signup. The Form does not have a name attribute. If the form has only one of the two attributes (name and id attribute), enter the corresponding attribute in the Name or ID field and the other field can be left empty.
If the form does not have both the ID and Name attribute, leave both the field empty. Freshmarketer will identify the form in your web page as you give your webpage URL. If the webpage has multiple forms with no form or id attribute, the first form will be loaded for the Form Analysis.