I'm confused on Kirchoff's loop rule. I know how it works. But I have no idea on which direction the current flows, and I'm getting mixed up on the signs of the resistors and currents.

Kirchoff's loop rule is nothing but Kirchoff's voltage law/ Kirchoff's second law, when applying KVL you must identify a closed loop and decide in which direction to go around it clockwise or anticlockwise, if the final value of current is positive it means the direction of current which u have taken is correct if the value of current is negative it means u have taken opposite direction of current, But in both cases whether u have taken current direction in clockwise or anticlockwise answer will be same only polarity will be changed.