how to store my own control's value in Asp.NetConfiguration database using CreateUserWizard?)

i am facing a problem in createUserWizard.
my application having that fields which is not in builtin createUserWizard control but i have to do
it through Membership Api.
e.g: CNIC (TextBox),VehicleModel (TextBox), vehicleType (DropdownList).
how can i save these values when i  ll click the Register (Button) from CreateUserWizard control.?

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