Campaign:
Was not too hard for a curling achievement. It's harder to explain, actually. You will have 4 stones and you have to hit 3 "x"'s. First, I would go for the upper left/right. You have to shoot with the help of the mini map at the top left corner. The red little arrow, is your best partner here. For the first (left) stone, you have to put the red arrow close to the end of the right side. And then press "A" and drag the arrow to the left, where the X is. Power: Beginning of 2nd blue fat line. Don't mop.
For the second stone, just do the same thing, but on the opposite side. Same power and everything.
If you got those 2, it's a piece of cake. For the 3rd stone just leave the arrow straight as it is and push "A". Power: In the middle of the first blue line and the red line.
Achievement unlocked!