Clouds & Sheep 2

For people like me who prefer a text based explanation of achievements, rather than a video you have to watch and listen to:

You need at least 2 sheep, and the winter area unlocked.
Go to the Winter world (with the snow).

Select a sheep, with your cursor over it hold LB and release - it will pull their tail and "ping" roll them across the screen, rolling up snow and turning them into a snowball.
(Make sure the path in front of your sheep is clear of obstacles - if they hit something prematurely, it won't work).
They will stay stuck in the snowball for a little while.

Select a second sheep and use LB to roll it into a second snowball.
Use A to carry one snowball onto the other, and it will turn into a snowman! You can quickly break it apart with RB if you like. Now just repeat 11x for the achievement!

(Tip: making a snowman using two baby lamb snowballs (not adult sheep) as the head & body will also get you a second achievement.)

Hope that helps :)

In my video I show how to make snowmen and baby snowmen to get

After unlocking the Winter World, make sure you have 2 sheep.

Hold LB, which will pull the sheep's tail and release LB to send your sheep rolling into a snowball. Repeat with the 2nd sheep.

The Fastest Way to get 11 snowmen is to pick up one of the snowballs and stack it on top of the 2nd. You can then pick up that top snow ball (should be in your hand and off the 1st snowball) and stack it back on. Remove and stack 11x and you'll get it in seconds.

TIP: You'll notice the snowman's appearance changes every time/every other time you stack the snowball on top of each other. Took me 5 seconds, and you DO NOT need to break the snowball and continuously turn the sheep into a snowball via pulling their tail.