Go to Bed

"Go to bed" means go to the bed AND lie down. You should only need to say "Go to bed".
Put a bed, blanket, or towel 6-10 feet away from you. With your dog beside you say "Go to bed!" and then together go to the bed. Have your dog lie down on the bed, give her a treat, and praise. Repeat many times. Later on, try sending your dog by herself. At first, make sure that someone is waiting at the bed with a treat. Later, your dog will do it herself, and you will walk over to her while she is lying down and reward her.
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It will take many repetitions, but she'll start to figure out that going AND lying down on the bed will get her a reward. It's important that your dog knows how to lie down. At first you might have to say Lie Down real softly to get your dog to go down, but try not to use it very much. What you want to say is "Go to Bed". Remember, "Go to bed" means go to the bed AND lie down.

The Trick is in the Training: 25 Fun Tricks to Teach Your Dog, by Stephanie J Taunton, Cheryl S. Smith
From an Amazon.com reader: This is a terrific book, escpecially for beginners. The book is very well illustrated with bright, clear, color photographs. The instruction is easy to follow and fun to read. There is a good variety of tricks in which to teach your dog. It is a very FUN book that makes you want to start training your dog right away! Note: This book is very simply done and should be readable by 4-6 graders.