Think I rerolled like 15 - 20 times before I got an SS mage. Just put on a podcast or video to watch, the tutorial doesn't exactly take much attention or skill.
A good start will be a big help (and possible shitty rolls later on won't be as upsetting)
Yeah, I got a podcast running. Anyway, sixth reroll yielded S-Rank Sha'plar the Witch. I.. don't think I have any more rerolls in me today.