^^^ This.

Moving your seat rearward will assist you in this, also there may be a need to slightly lower the nose of the saddle to adjust your fit. You'll know when your glutes are engaged throughout your pedal stroke after about an hour in the saddle; your muscles will be talking to you.

I had a recent fit and this was one of the things we addressed in order to maximize my power stroke and yes, I noticed a huge difference in both power and pain.