Start with a six-membered carbon ring (non-aromatic), numbered C1 through C6. The ring contains two double bonds: one between C4-C5 and another between C6-C1; all other ring bonds are single.

Substituents:
- C1 bears an acetyl group, i.e., the ring carbon bonds to a carbonyl group, and the carbonyl carbon further bonds to a methyl group.
- C2 is gem-dimethyl, carrying two methyl groups on the same carbon.