Crop rotation can be effective in discouraging pests and preventing soil-born diseases in vegetable gardens and annuals beds.  Crop rotation , combined with adding organic matter each season helps the soil replenish those depleted nutrients.  When practicing  rotation you basically don'ts grow the same plants, or even related plants (like peppers, eggplants, potatoes) in the same place for at least three consecutive years.  Keep track of your garden from year to year to ensure a successful rotation plan.   I keep track of this on the computer within a table using MSword (example below).   This way I can easily rotate and know what is where when.

I basically have raised beds because of where I live in Northern California. 

I basically lay out what I'll plant in each of the raised beds, grouping things appropriately based on our calendar for planting.   My planter 6 is for permanent plants like  my rhubarb, artichokes, asparagus and perennial herbs.  My planter 7 is also permanent as that is where I have my strawberries.   I list what is in each planter and then the following year I'll put what I had in Planter 1 into planter 5 and rotate everything up by one.  Below is a copy out of "The Book of Outdoor Gardening" by Smith & Hawken.