Time for action – pressing B for border selection
The border selection works similar to the Marquee tool in Flash or Photoshop, stretching a border around the vertices you want to select:
Press the A key once or twice so that everything is deselected.
Move your cursor above and to the left of the cube.
Press the B key. Notice that the cursor has dotted lines coming out of it—crossed lines as on the left-hand side of the previous illustration.
Hold down the LMB while you drag the cursor down and to the right. Any vertices within the border will be selected when you release the LMB. Just select the vertices on the left-hand side.
Press the B key again. Make another selection, but start at the bottom-right and move to the top.
Now, press the B key, move over the vertices you have already selected, and press the MMB as you drag the cursor.
What just happened?
The B key starts border selection. You hold down the LMB while you drag the cursor. All the vertices within the border get selected. Each time...
