@HappyThursdays @Puppypuppypuppy I don't know if I'll be able to explain it very well. So first we worked on stopping them grabbing for treats, so practised giving them treats and them taking it gently (with the treat in your fingers like a claw if that makes sense).
Then step 1 was get them to sit and hold a treat over their head. Start high up, if they sit nicely and don't grab they get the treat. Gradually reduce the distance between your hand and their head.
Step 2 - sit down and place the treat on your knee. If they don't grab it, reward. Again, move closer to make it harder.
Step 3 - place the treat on the ground
Step 4 - drop the treat on the ground from about an inch high
Step 5 - drop the treat. Rather than picking it up and giving it to them, release with 'okay' or another word so they know it's okay to move
Our trainer work with 3 D's, so gradually build up distance by getting closer, duration by making them wait longer before rewarding, and distraction by practising in different locations. It took us a few weeks to get to this stage but she is honestly brilliant now. Day 1 she was jumping up for the treat over her head.