This is not one I can relate to, since I've always been able to relax. I work at it from the physical side, and that brings my mind into focus. I can think of a muscle and notice its current state of tension and then just relax it. Like gripping something and letting go. If you find this hard, you can start by picking the muscle, noting its state, contract it a little then let it relax.
That was the way I used to do it, and still for single muscles I'll do it. If I choose to consciously relax, which I seldom do, I use the wave technique. Where you have a wave of relaxation sweep from your head to your feet.
Now here is something I've done in the middle of meditation and wanted to relax even more. Now it's not SFQ but something I just did when doing a sitting meditation. I use the waves in rythmn with my breath. I inhale and think about my head area, then on the exhale I move my focus through my body to the lower dan tien.Then as the exhale is ending I bring my awareness out of my body.
Doing this with a verbal thought of RE (inhale) LAX (exhale), have been very powerful for me. It deepens my meditation, but I only use it after I've gone into a meditation. I don't use it for entering a meditation.
Sorry, that's gone off topic again.
As a last note, it deepen my sense of energy but it doesn't bring me deeper into the emptiness. Ooops, that may be my labelling problem.
You are perfection.
Iam2