I wish somebody would build a Square Foot Gardening grid that you can insert into a raised garden bed to mark off squares, but until this is available, if you want to use the Square Foot Gardening method, you will need to devise your own method for marking off squares.
When growing vegetables in raised garden beds using the Square Foot Gardening method, your beds will need to be sectioned off into one-foot sections called planting squares.
This type of planting will discourage insects and specific vegetable pathogens that can stay in the soil over winter and planting that same crop in that bed will infect the crop.
our limitations will go as far as your imagination takes you and the area of space you have to work the garden. There are raised garden bed kits available for purchase at some nurseries, home and garden centers, or on-line.