There is a lot of starch in the pot (the water turns starchy from the starch in the sago), as you cook the sago, so at some point, you will not really be able to see the cooked pearls. Instead, it will just appear like a gooey solution in the pot. This is perfectly normal. Once cooked, transfer the hot sago mixture into a strainer and literally wash them in running water for a couple of minutes until all the excess gooey starch is washed away. Use a spoon to mix the pearls as you wash them. You will begin to see the sago pearls lose and not stick to one another once the starch is all washed away.