Sago palms produce male and female flowers, and for the female to produce seeds, the male flower needs to pollinate it. These seeds can then be used to propagate more sago palms. However, the energy it takes to make seeds takes away from plant growth. Removing the flowers can stop the plant from using that energy for making seed and use it for growth instead. Typically, though, sago palms only flower every two to three years.
Wait to remove the male sago pale flower, the cone, when it fully opens, revealing the pollen inside. Wait this long if you plan to use it to pollinate the female flower. If you're not using the male flower for pollination, you can remove it at any time.
Grab the cone at the center and snap it off. You can also saw it off at the bottom.
Remove the female flower by removing the entire flower stalk before the flower expands. It's difficult to remove it once it is fully grown. Use a saw to get it off, but do not remove green fronds in the process, which will harm your sago palm. If necessary, just leave the bloom alone.