Many documents are still printed on paper and their interaction is disconnected from the digital paper representation. Conductive ink allows to print documents with embedded electrical circuits. We developed several layouts to add interactive elements, such as tick boxes or signature fields, to paper documents. In this paper we propose several techniques to enhance classical paper documents by an additional layer of conductive ink. Through this layer the documents maintain their traditional properties and affordances but receive new interactive capabilities that transform them into smart documents. Attached tiny computing elements enable interaction with the paper, such as sensing selections on a form, detecting a signature, or traditional office equipment (e.g. paperclip). Additionally to the layout suggestions we show different ways how the computing unit can be connected to the document and how multi-page documents can be connected to a single computing unit.