By Zara Woodcock Britain’s Got Talent judge Amanda Holden revealed how co-star Simon Cowell gets ready before they start filming for the show. The music mogul, 64, is known for wearing the same outfits over the years. Fans have gotten used to the star wearing his iconic bootcut jeans and aviator sunglasses. In the latest season of the talent competition, Simon has been wearing more compression tops but makes sure to keep to his usual colours. During a recent chat, radio host Amanda explained why Simon switched from his button-up and low-cut tops to his new fits. She said he spends some time be…