Harper and Harley The blog was founded by Sara Donaldson from Australia. The 25-year-old is a marketing graduate from the University of Brisbane in Australia, and she has an interest in fashion, relying on her blog and her Instagram to attract the attention of many big brands.

Donaldson is what is now known as an "influencer" (influencer). She has 70,000 readers per month on her blog and more than 700,000 Facebook and Instagram followers. She knows the impact she has on her readers, she says: "My readers read my blog, follow my Instagram and buy what I tell them is on trend, and I know that everything I put on my blog and Instagram will turn into sales.

Donaldson's website not only makes people drool over her beautiful photos, but also allows them to click directly and buy her clothing and accessories. The big companies are starting to turn their attention to these social stars so that their brands can be exposed in front of these stars' readers.

Beauty brand Estee Lauder liked Donaldson's aesthetics so much that it approached her and hired her to provide content for its social media channels. Other beauty brands such as L'oreal and Charlotte Tilbury have also collaborated with Donaldson, while fashion brands Country Road and Qantas Airways have also "heard of her" and even Mercedes-Benz has provided her with a car to travel in and asked her to take photos for uploading.

Australian brokerage Remarkables Group broker (Lorraine Murphy) said these successful social media opinion leaders are full of money, "Some can generate $40,000 a year for a channel, and some can even earn $500,000 a year. Some can generate $40,000 a year from a single channel, and some can even make $500,000 a year. However, tens of thousands of people post or image on Facebook, Instagram, blogs and on a daily basis, and only a few are as successful as Donaldson.