Improving geometry for applied math?

Hi everyone, I am currently studying engineering. I am having some issues in applied math (dynamics specifically) where I understand the concepts quite well, but some of my geometry skills are lacking. An example of this is where I have a curve and an object moving around the curve, then some force acting on the object. I then need the calculate the normal and tangential components of the force to the curve, but I just don't really know how to work through it mathematically? If I mess around on a geometry calculator with i can kind of see why certain angles are used to determine certain components but I just wouldn't be able to work it out on my own.