The first step is to calculate the dimensions on the inside of the garden bed, which is the length and width that is actually usable for planting. If you bought your beds from a commercial source, then chances are, the interior dimensions are probably a little less than the advertised size.
Some of the other benefits of raised beds are: reachable - less bending and stretching gives the gardener easy access and makes maintaining and harvesting less of a task to perform; drainage - because the soil is above the ground it will not become compacted during heavy rains and will drain properly in preventing water-soaked soil;
Each planting square has an address used to identify the square. While the methods for addressing vary, one of the simplest is to use letters for columns and numbers for rows, and the combination of the two identifies the square.
Number of anchors per board: (Usable Length / Spacing for anchors) - 1. For my beds, I need 7 separators for each 8 foot board and 3 for each 4 foot board.