We know $F(0) = 0$
Okay, I just need some intuition on how to do this. So far, all I know is that the slope of $F(x)$ is always positive, therefore I should not have a negative slope anywhere on my graph. Other than that, I have no idea what I can do to graph $F(x)$ given $F'(x)$.

In the following figure the red line represents $f$. $f$ is non-decreasing since the derivative is non-negative. $f$ has $0$ slope and slope $2$ as show (red numbers). $f$ has inflection points where ever $f'$ has local minima.