The golem notices you charging right away. "Intruder detected! Stop running, pony. You will be incinerated shortly."
It charges its weapon.

Athletics: Jump on the golem (fast).

Perception: Avoid the discharge, then jump.

Jump on the golem.

Strict Mode (In Strict Mode, the game will not show you options that require a skill you do not have. In non-strict mode, these options will be greyed out but you can still cheat and access them. You can switch modes at any time.)