There's software that will animate for you.
Two packages I've used myself are Crazy Talk Animator and Moho Studio. How this software works is you place "bones" in your character and then can animate it by just pulling its leg left or right. You also only need to animate the first and last frames. The software fills in the gaps - but you can tweak the animations.
They include animations (like walk, jump) that you can apply to a rigged character and easy ways of creating a character directly in the software.