Don’t assume. Just because your friend’s dog loves a tennis ball, doesn’t mean your dog does.
If your boss asks you to work hard, and gives you a handful of sand on pay day, you probably won't be looking forward to working again next time he asks you to. In order to be able to use something as a reward, your dog needs to feel that the reward you are offering him, is worth pursuing. The more valuable and the more motivating the reward is for a dog, the more enthusiastic he will be to work in order to get it.
Don't assume that your dog automatically likes certain things. Also, don't assume that your young dog likes all the same things as your older dog did. Spend time getting to know your dog, and find out what kinds of things he loves the most:
- Test different kinds of treats, like ham, cheese, chicken, boiled intestines... Smells are very significant in the canine world, and that's why a meat ball you quickly warm up in the microwave oven is probably much more interesting than dry kibble.
- Don't choose toys according to your own preferences in colors and materials. Test and find out what kinds of toys your dog likes; rubber toys, plastic toys, furry toys, squeaky toys, hard or soft, big or small... Some dogs appreciate an empty plastic bottle more than an expensive toy from a pet store.
- Some dogs love to be touched, while others become distressed if you pet them. Read your dog's gestures, and see if he finds tactile interactions rewarding.
Have fun training and enjoy every moment with your best friend!