Use space or mouse click to land kapsulas, preferably into a free slot. After 10 kapsulas are landed, you can skip to the next level by pressing Enter or mouse click to the rectangle with NEXT. Next level will be faster, so try to land as many kapsulas as possible while the speed is still reasonable.
Originally the game was made for Sinclair ZX81 with 1KB RAM, in machine language. It won the 3rd price for "Best program" in competition organized by Jugoslavian popular science magazine "Galaksija".