The first step in solving the equation \( \frac{1}{3}x = -9 \) is to eliminate the fraction by multiplying both sides of the equation by 3. This will give:
\[ 3 \cdot \left(\frac{1}{3}x\right) = 3 \cdot (-9) \]
Simplifying both sides results in:
\[ x = -27 \]
So, the first step is to multiply both sides by 3.