How do you avoid streaks under the film?

Answer 1: Streaks under the film are often caused by not using enough slip. 

Answer 2: The soap may be drying before you put the film on. While this usually goes away as soon as you squeegee the film, you can try adding more soap/water solution when applying the film. 

Answer 3: These streaks almost always dry up and disappear after a few hours.

Answer 4: You might want to switch to baby shampoo.