This part is on how to add the skin into your actual game. *Note: this will not work if you play offline as the skin is cloud-based. To upload you skin to your game you must first go to the website minecraft.net.
Once there click on Login and (obviously) log in. Once logged in as you, click on the link called "profile' at the top of the page. Once now once again look at the picture notes to get the full picture (lame pun) After following the steps listed above you can change your skin as many times as you want, with no charge, and make your character look however you please!
Thank You for reading my 'ible on how to make and install a character skin in Minecraft. I hope you liked it.
You can also just download skins of the internet but where's the fun in that? You're a maker aren't you?!