User Level: 

After you add the field you will see the element details screen.

Field Key

Pay particular attention to value you use for the field key. You will want these to be unique across all of the forms you create. If you plan on creating a number of forms you may want to prefix each field key with a short name of the form. For example "survey1_first_name". Only use lowercase and underscores in field keys.

Default Value

If you want the field pre-filled with a default value then enter it here.

Description

Enter any text as an aid to the person filling out the form.

There are a number of other options in the Element Details

Validation

You may have already made the field mandatory. This screen includes the options to make sue the entry is unique across all submissions, and to set a maximum length for the input.

Display

These options control how the field is displayed on the form. Note that the default is to place the label above the field. If you want in to the left select "Inline" from the menu.

Tokens

Tokens are code shorthand that will expand into a value when the form is displayed. These will not always be that useful. This example will pre-fill the e-mail field with the e-mail address of the person completing the form, but only if they have logged in to the site with their ONID. A more useful example might be the date token to fill in the current date.