Just a brief insight to how to how I sprite usually.
Top one Rupsen, I set out a 96x96 border to know how big I need to make it relative. Then I just doodled the pose.
Second one I didnt doodle a pose just started pixelling straight from the face. It was TOO big so I had to reduce it in size.
Third one was a lot harder to do, including a slight repose halfway through so there were a lot more variations and "assets" created to aid in this.