Several joint-less coil structures were developed in the past decade that allow the coil made of HTS coated conductors operate in persistent current mode (PCM) at 77 K. The PCM coils could operate as the main magnet or shielding coil for small MRI/NMR or in maglev at 77 K to simplify the cryogenic system and lower the cost. While after the PCM coil is magnetized, the field trapped in the coil will endure an initial fast decay for several hours due to the current density redistribution and flux creep. In this paper, we tried to find effective methods to shorten the initial fast decay process and stabilize the trapped field as much as possible. An electromagnet is used to magnetize the joint-less coil with field cooling and zero field cooling method. Then the field reversal and field shaking are conducted on the coil to accelerate the current density redistribution process. The result shows that the initial fast decay process can be effectively shortened from several hours to tens of minutes, which can reduce the magnetization time in real application.