how to make a good base

First, put your most important item(s) in the middle, in a symmetrical shape. This can be anything from one mortar to 9 towers. Next make a wall around them and put 4 symmetrical squares made of walls with the inside being a 6x6 area. Then you insert your 3x3 towers within the 6x6 area or make more squares and the insert the 3x3 towers.