If I recall correctly from our puppy training class:
1. Ask your dog to sit.
2. with a treat in hand, hold the treat in front of your dog to get his/her attention.
3. bring the treat down to the ground.
The idea is the dog should lower themselves to the ground and as he/she lays, praise and release the treat. Rinse and repeat!
That's what I remember doing for Java and Lilo and it worked for them. Good luck!
1. Ask your dog to sit.
2. with a treat in hand, hold the treat in front of your dog to get his/her attention.
3. bring the treat down to the ground.
The idea is the dog should lower themselves to the ground and as he/she lays, praise and release the treat. Rinse and repeat!

That's what I remember doing for Java and Lilo and it worked for them. Good luck!