Go HERE, make sure you click EVERY crimson icon!
There is a couple places that have some trivia and the answers are
1. Guns blazing
2. Boomshot
On this screen you will be required to drag and place positions, they are as follows
3. From left to right, engineer, assault, medic, scout.
At the end you should have a bar that fills up 100% and you can redeem your skin right then and there
