Add powdered sugar a little at a time
Chill the frosting in the refrigerator
Beat in softened butter
Mix in a small amount of cornstarch
Add cream cheese for a thicker texture
Whip the frosting longer
Reduce added liquid next time
Use less milk, cream, or water
Add melted and cooled chocolate
Fold in cocoa powder for chocolate frosting
Add meringue powder
Let the frosting sit to firm up
Use instant pudding mix
Add a small amount of flour if appropriate
Refrigerate the cake after frosting it