Customize the current magento onestep checkout page

Question

Need help in customizing the existing onestep checkout page so that billing/customer info form will be included within the payment select section.

For Example,

If Customer has chosen Card as payment option then along with Card Details form fields it should also display billing information fields(First name, last name, email, country, zip, password, confirm password.) as well.

If customer has selected paypal as payment option then fields(Email, Password, Confirm password).

Basically, we are trying to reduce the number of steps and speed up the checkout.

Answer 1

Use the following

public function index( $category_id = null )
{
    if (!$this->KnowledgeSolution->KnowledgeCategory->exists( $category_id ))
    {
        throw new NotFoundException(__('Invalid Knowledge Category'));
    }
    $KnowledgeCategory = $this->KnowledgeSolution->KnowledgeCategory->read(null,$category_id);
    $this->set('KnowledgeCategory',$KnowledgeCategory);

    $this->Paginator->settings['contain'] = array('Users','KnowledgeReply'=>array('Users') );
    $this->set('KnowledgeSolutions', $this->Paginator->paginate());    

    $this->Paginator->settings = array('conditions' => array('Product .title LIKE' => 'a%'),'limit' => 10 );

    $this->set(compact('data'));
}