You can use the Sculpt Tool to sculpt, or if you want to use edit mode(its what I did) you can see the gray circle a the bottom of the 3d view(in edit mode), to the left of the magnet
Click it, and select enable
Now when you move, scale, or rotate vertices, it will move vertices in an area and not just the ones you have selected. I suggest using the keyboards hotkeys G(move), R(rotate), and S(scale), so you can easily use the scroll wheel on the mouse to change the area affected