I have 2 forms that my users are using to sign up with. What can I do to preserve the first form's information while they move to the second form and then after they fill out the second form then write it to the database?

I have been trying cookies but can I add to the current cookie the second form's information? Like writing to a DB but a cookie instead?

If I have to write to a DB after the first form has been filled out, then how do I add the second form to the correct record?