Methods and apparatuses for improving uplink transmissions in a wireless communication system are disclosed herein. In one method, a user equipment receives an indication indicating a type of data that can be transmitted using a cooperation mode. A first data is transmitted using the cooperation mode, in which the first data belongs to the type of data using the cooperation mode based on the indication. A second data is transmitted without using the cooperation mode, in which the second data does not belong to the type of data using the cooperation mode based on the indication. The cooperation mode is enabled when transmitting the first and second data.