Here is the Problem Solving Approach for drawing FBD's and thereafter selected solution to the problems from Nootan Physics...
How one should draw the Free Body Diagram's (FBD's), remembering these points would always help you to do that.
Watch these video's to understand the basic steps to be followed while drawing free body diagrams, they will build your approach towards numerical solving:
Different approach for finding the acceleration, considering the different connected bodies as a system and neglecting the internal forces...
