How can you stop a dog from pacing up and down?

get a friend with a dog here is what you do:

1: have your friend hold there dog at the opposite side of the field you are at.

2: Let your dog see the other one

3: if they bark, run, or pull, block their vision. don't let them see the other dog.

4: Once they calm down, let them see the dog again. if they bark run etc. block there vision again

5: Keep this up until they stop barking at the other dog from that distance. Then, walk forward until they bark...

6: keep this up until you are up next to your friends dog. Let them greet and continue doing this for as long as you need for your dog to help them

Hope i helped. Remember, it won't happen right away, keep at it! :D