I am new to making cakes and frosting. I am making buttercream frosting using butter crisco and clear vanilla. The bride has requested dark royal blue for her cake. I have used both wilton royal blue gel and americolor softgel paste. I have used almost half of a 1oz jar and still cant achieve a dark blue... What do I have to do to achieve a darker blue? I feel like im getting nowhere and have to make enough frosting to cover a 4 tier cake, please help me!!!