What you wanna do is:
1. Start up Tutorial
2. Skip past the tutorial messages by pressing
3. Go up the stairs and make a left at the fountain
4. Make another left and grab the shovels out of the chest next to the anvil
5. From here, go back down the stairs, make a right, and run straight pass the fountain and farm
6. Make another left and use this area to collect dirt. Collect lots of it!
7. When you collect good 200 or so, make your way to an area that has a crafting table and a structure with a ladder on it. It's not far from where I told you to dig.
8. Equip the dirt, climb onto that structure, look down and jump. As you jump, pull
. A dirt should appear under you.
9. Repeat until you're above the clouds. The point to this achievement is to gain enough momentum to where to get propelled upward 30 blocks or more.
10. When you're super high up, walk off the edge and try to steer yourself onto the slime blocks. If you have the momentum needed, you'll be launched back up by 30 or more blocks. The achievement will take a few seconds to pop.
[Video is being edited at the moment]