This is a nice tool that you will help you with creating pixel art, but you have to pay $20 to use. Use this link to travel to the download: Aseprite – Animated sprite editor & pixel art tool
If you do not see a download either scroll down to the bottom or press Buy Now at the top.
This one is quite easy as the once you purchase it, the website will give you a downloadable link that will then take you step-by-step on the process of downloading it up to using it