Establish the coach's authority

You decide it's time that Taylor learned that she was not superior to every woman she met. First, Ms. Samson needed a slight change in attitude - instead of thinking of herself as one of the girls, she needed to think of herself as above them. You decide that more of an age gap will help with that, and advance Ms. Samson to 40 years of age.

"You're definitely going to learn your place, you old hag.", Taylor spits at the now significantly older woman - who is showing signs of her age.

The next step is that Ms. Samson should have become even more fit as she grew older - her body tighter and stronger. But also her figure more mature and busty.

You watch as her breasts become firm against Taylor's and then begin to grow larger. Her entire body becomes toned.
Her skin smooths a little - making her look more like 30 than 40.

She is now pressing Taylor backwards, much to the head cheerleader's disappointment.
In moments, she has Taylor pressed against the wall and her still growing breasts are now beginning to compress even Taylor's large, firm bust.

You decide that Ms. Samson needs to be taller as well - her face more beautiful than Taylor - smarter than Taylor as well. Really, just better than Taylor in every way, by a noticeable margin.

When you're finished, the guys at school will still be hot for Taylor - imagining what it's like to get with the head cheerleader, but they'll be fantasising about Heather Samson.