Rigged Sprite Animation Problem

Hello,
First of all I am new to Unity and I usually good at programming and stuff. But, I am trying to move to designing a bit. So, I am trying to create a Rigged 2D Character in Unity for my platformer game. The problem is I have no idea how to animate a rigged sprite easily. Please help me in this regard. Thanks.

 

I like design, for my project, I create animation 2d (roughly 4 image to race 1 for shock etc etc)
example:

 

Doesn't creating spritesheets take a lot of time and does it offer you all you want to do? thanks