A method for non-orthogonal multiple access (NoMA) transmission is provided. In an embodiment, a method in a network device for transmission of a NoMA signal includes obtaining information bits. The method also includes transmitting the NoMA signal. The NoMA signal includes one or more layers. The NoMA signal is generated according to the information bits and according to a set of signal processing operations selected from a plurality of signal processing operations. At least one of the set of signal processing operations is layer-specific or UE-specific or a combination thereof.