Buttercream Frosting how to (very yummy)

4 cups of sifted Powder sugar 2 tsp of meringue powder 3/4 cup of Butter 3/4 cup of High ratio shorten if need be you can use crisco but don't use to much water 1/2 tsp of Vanilla Flavoring 1/2 tsp of Butter Flavoring a 1/2c and 1/4c I think to