There are lots of ways to train the weave poles. What we have here are channel weaves. You start out with the weaves wide open and run the dog down the middle. Then you gradually close them until eventually your dog is doing them all lined up.
You will want to take a few weeks to do close them down, practicing a bit each day. Start with six poles and then add two poles as your dog has mastered each set. Go from 6 to 8 to 10, etc.
If you find your dog stopping before the last pole to look back at you or to run to the next obstacle, try throwing a toy or a treat past the last pole on the side they should come out on–they will be focused on that and go all the way through.
If your dog makes a mistake or misses a pole, this just means you went a bit too fast. You can go back and make it easier by opening the weaves up a bit again, then try again to close them some.