The star tip creates the most celebrated, easily accomplished decorations, making the star fill-in technique a perfect option for a beginner’s project.
Hold the decorating bag at a 90° angle (straight up) with star tip about 1/8 to ¼ in. (3.18 – 6.35 cm) above surface. Squeeze the bag to form a star. Stop pressure and pull tip straight up and away.
Pipe a row of stars uniformly close together in a line, adjusting the tip position slightly each time so that the points of the stars interlock and eliminate gaps.
Continue piping additional rows, adjusting the tip position so that the stars are piped between the stars of the previous row to fill in the cake surface without any gaps.