The lovely Pippa Middleton gave us a good lesson in what to pack for a European mini=break last week when she visited the Spanish capital Madrid with a group of friends (including an ex-boyfriend!) Pippa looked fabulous throughout the trip, with an impeccably chosen summer wardrobe of neat dresses and cool seperates.Here are a few tips for channelling Pippa’s style this summer. 1. Choose classic separates for the airport experience. Pippa’s simple vest and cardi combo are comfortable for short air travel, and the cute cardi will combat the sometimes chilly feel when on a plane. 2. Invest in a wear-anywhere dress. This dress is the perfect piece if you…