Now that you have your plan, it's time to get the materials.
The frame can be made out of just about anything: rocks, logs, bricks, lumber, etc. I chose to use landscape ties because they are inexpensive, durable, look good, and happen to be 8 feet long!
If you have good soil, you can use it in your raised beds. Otherwise, you can purchase soil. Before heading to the store to buy it one bag at a time, see if there is a landscape supply company nearby. I was able to buy a "loader full" and fill up my whole bed for a fraction of what it would have cost.
Do you have an existing sprinkler system? If so, you can replace the sprinkler head with a hose! Attach a regular hose to span from the sprinkler head to the raised bed, then a soaker hose to use in the raised bed.