Once you have copied a Google Form to your Google Docs, you may edit it.
Open the Sheet that you copied.
Click Form > Edit form.
This opens the form in a separate window for editing.
Edit Form Name: Click the form name (upper left side). You many rename it by typing here.
To edit questions, select the questions tab at the top of the form, then click the six dots that appear when you hover your mouse over a question.