Driven by the ever-growing need for developing low-cost, easy-to-use, noninvasive diagnostic tools, biomedical devices that can be integrated on human skin or textiles have begun to emerge. These `wearable' devices should couple electronics directly to the human skin and detect a variety of biologically relevant signals such as neuromuscular activity. In this work, we develop a simple, low-cost and customizable device to perform electromyography measurements based on electronics fabricated on tattoo paper. The electrodes are based on the conducting polymer poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT: PSS) and inkjet-printed on the conformable tattoo paper. Addressing the integration challenge common to such flexible electronic devices, we connect the tattoo electrodes to the acquisition system through a textile in the form of a wristband comprising printed PEDOT: PSS contacts. While the textile wristband conforms around the `tattooed' skin, it enables a reliable contact with the electrodes beneath. Weshow that this tattoo/ textile electronics platform is able to monitor the biceps activity of the arm during muscle contractions lasting for a period of 7 h, with comparable performance to conventional biopotential electrodes and without the use of gels or expensive metallic materials. Combining the tattoo electronics with the electronic textile improves the communication of skin-like electrodes with external electronics, renders a reliable and versatile system for detecting biopotential signals critical for myoelectric prosthesis, muscle injury prevention and/or detection.