Sago's are cool plants. I have one that is almost 30 years old. The older they get, the cooler they get. Just like me...hehe
Each year, the plant will grow another "set" of crown leafs. You trim off the previous years growth as the new comes in. Careful trimming for consistency in shape is most important with sago's. I use a very sharp pruning shear. The base of the stalks are very fibrous and pretty tough. You can slice yourself very easily with these stalks. Be careful.
A handful of manganese sprinkled around the root zone on the surface of the ground will keep them real healthy if you give it some half strength Miracle Grow via watering about four times a year.
Mine has a leaf span of about 10 feet in diameter now and has spawned about 12 babies this past year. As soon as the side growth clones are large enough to clip, I'll have 12 more sago's.
Good luck with yours. You'll want to put it into a nice big decorative container at least 5 gallons in size. They don't like to be transplanted. It's better to give it a nice large beautiful home to live in for the rest of it's life. The container and the plant become "fixtures" in your life.
I know families here that have plants that are more than 100 years old. Those plants are priceless. Four generations of family have had photos taken next to that plant and it's beautiful planter. Pretty cool.