First off I'd let the ears alone till she's 12 to 14 weeks. By then they should either be erect or half way up. Doing too much to the ears before then can actually damage the cartilage to where they will never stand up.
If by the time she's 14 weeks and they are really flat down, then this method is an excellent one that works if there is no damage done.
Top Taping Yorkie Ears Taping Yorkshire Terrier Ears Stand Erect Yorkie Ears