What program are you creating your sprites in originally @havie? There are a couple of great programs that are focused on sprite creation.
http://grafx2.chez.com/[url] Is closest to our favourite programs on the Amiga and supports older bitmap and palette formats.
https://www.aseprite.org I have not used, but looks amazing. It has a big community as well.
https://www.cosmigo.com This is a high end option which I have not used but gets loads of good press and community use.