Showpony Deep Cleansing Shampoo 1Litre You’d never invite peeps over for dinner without a little spring cleaning first, and you shouldn’t even think about hair extensions before making sure your strands are squeaky clean either. What you need is a gentle yet effective shampoo to remove all traces of product build-up so you’re ready to roll with your extensions. How I work: massage through wet hair and scalp. Rinse thoroughly and repeat if necessary.