Terraforming

Shaping land in Minecraft can be a lengthy process. Terraforming layers of dirt and smooth stone removed block by block is tedious and strenuous. Clearing the face of a cliff/mountainside can be very time consuming to do alone.

TNT can be an effective way of clearing unwanted blocks, burrow throw 5 blocks of area you intend to decimate. Place the explosive, checking their is a safe passage out. Put a lever next to the TNT block, when your satisfied that your safety isn't compromised. Right click the lever and double tap the 'forward' button (w) holding it down and jump if necessary to clear blocks in your way. 1.7 seconds after the lever is pulled, the TNT block will duly explode.

The old fashioned method of mining with a stone pick to flatten land can take up hours of game-play could bore you. Creating a tunnel is a sensible option when you want to clear a hill that lacks depth. Say only  20-30 blocks wide and 10-12 blocks tall. Politely asking players that are willing to help excavate land is a sensible option when excavating hundreds of unwanted blocks that are a hindrance to you.  

Terraforming done properly, entails the players molding the land to suit a construction/fortification, perhaps a project. Covering the ground with dirt in place of ores and smooth stone uncovered, merges the area you have Terraformed so that it looks natural and the ground returns to normality, eg: grass and sand blocks as first layers.