Complex sentence: As the popularity of his blog grew, in mid 2012, he got help from two unpaid assistants and started a Tumblr page, he was also featured in "Vogue" in the same year.
Split into simpler sentences: As the popularity of his blog grew, in mid- 2012, he got help from two unpaid assistants and started a Tumblr page. He was also featured in "Vogue" in the same year.