Log into a Google Account and click New > More > Google Forms.
Build the form fields required using the editor.
If the form was built with an account that is part of an organisation then click on the cog and unselect the option that only members can complete the form.
Set the form to save the responses to a spreadsheet by clicking on the Responses tab, and click the spreadsheet icon. The popup provides the option to save this form data to a new or existing spreadsheet. By selecting existing it allows multiple forms per spreadsheet. Follow the prompts to complete this task. This is a good time to save some test data to make sure it is all working.
Optionally the web app may wish to set some pre-filled responses in the fields. If that is the case go back to the form and click on the three dots dropdown menu, then click
Get pre-filled link. This will load the form in a special mode where fields can be completed without submitting the data. When completing the fields use the label name as the prefilled value. Then save the URL which will have parameters similar to
entry.123=labelname1&entry.456=labelname2. Save a copy of that URL for later.