The wording is tricky.
Every time you level up, you gain a point in every attribute. This is automatic.

You gain 3 Bonus Points at level 10.
You gain 1 Bonus Point every EVEN level (12, 14, 16, ...).
I ~THINK~ you gain 3 Bonus Points even 10th level (10, 20, 30) but I honestly have not been paying attention and this may be wrong.