Mochiko and 3/4 cup water should be thoroughly combined in a glass (or other heat-resistant) bowl. If it's too dry, add 1 Tbsp at a time extra water.
For 20 minutes, cook the mochiko dough in a steamer.
In the meantime, combine 3/4 cup water with sugar in a medium pot and heat until sugar dissolves.
Place the steamed mochi in a pot, add the sugar syrup, and cook at a medium-low to low heat. Cook, constantly mixing, until all of the syrup is mixed and the mochi turns sticky. Spend some time, but don't burn it.
Take the heated Mochi out of the saucepan and place it on a cornstarch-dusted sheet pan. Cut and shape as desired.