Complex sentence: Krogsvold created his YouTube channel in June 2007, using the name "waterflame89", after the last two digits of his birth year, first uploading a remix of "Freestailo", a popular meme during that time.
Split into simpler sentences: Krogsvold created his YouTube channel in June 2007, using the name "waterflame89", after the last two digits of his birth year. He first uploaded a remix of "Freestailo", a popular meme during that time.