I taught my boy how to fetch quite a while ago. You can train your people to fetch, too! Here are the easy instructions:
1. Bring a favorite toy to your person. This helps them realize that you want to engage in play with them.
2. People naturally want to throw things, so this is the easy part. If you'll watch them, you'll know that they throw things in the trash, throw things at spiders, throw balls to each other, throw things across rooms to each other to catch... Throwing comes naturally to them, so if you get a toy they like, they'll eventually develop an overwhelming desire to throw it. If the first toy doesn't get their attention, try another. Eventually you'll find one they love, and they'll throw it.
3. Once your person throws the toy, run after it. They love this part. It really makes them happy to see you run after things they throw. It goes back to that love of throwing. They like to see others appreciate a good throw, too.
4. Stand by the toy to mark the spot for them. Remain firmly in place until they come fetch the toy. If you move, they may lose it, and the game needs to be started over from #1 again.
5. If your person doesn't understand why you're standing at the toy, you may need to pick it up and take it back to them on occasion. This will show them what they're supposed to do. And just to keep them interested longer, you might want to pick it up and return it to them every 8 throws or so to keep them from getting too tired. People only have half the legs we do, so they tire easily.
6. Sometimes it's fun to run to the toy, mark where it is, and then run back to your person. This way you can race each other to fetch it since you both know where it is now. I find this is my favorite way to interact with my boy when we play fetch, but you'll have to decide what works best for your person. Each one is different, you know.
And above all, HAVE FUN. Remember, your people have to leave you at some point through the day to work, so make the most of the time that you have with them!