Where should I put my next vector point?

In Illustrator you should always keep your vector points at a minimum. When drawing the best rule of thumb is to add a vector point when you need to change the direction of your path.
 
Adding too many unnecessary vector points can make your file size larger and can make it harder to edit in the future. Regardless if you are drawing garments or any graphic design you should follow this tip!
VECTOR_POINTS