Don't forget the dash in my name, when you print it
It'll make me feel bleak like Jay's apprentice

from Ab-Soul (Ft. Jhene Aiko) – Nothing New Lyrics on Rap Genius

Meaning

He’d like for everyone spell his name “Ab-Soul” and not “Ab Soul” when they write/type it. If you don’t he’ll feel gloomy about it (bleak), like Jay-Z’s apprentice’s (Memphis Bleek) last name.

Finally, this is also a reference to Damon Dash, with him formerly being the primary producer for Roc-A-Fella Records, Ab-Soul could be saying don’t forget to mention who produces his music when you mention him. The reason why at the beginning of the song he says:

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