Sure :p. Rather than me sending it, I'll just post what I go through.
1. Either find an empty server or buy a vip server in order to take a screenshot with no one in it.
2. Join the game and position where you want to take the screenshot. When you take your screenshot, have the character in the picture stand on a flat color so you're able to color over your character easily.
3. Take a BIG screenshot. When taking your screenshot, have your chat and leaderboard closed. I recommend using either Lightshot or gyazo to take the screenshot.
4. Load up your editing software (paint.net works).
5. Place your image onto a wide display (3110 x 1500) and color over your character with the same color as the ground their standing on.
6. Save it as a JPG and make sure the size is less then 300 kilobytes.