When I first became a personal trainer I learned the "Super Slow" methodology:
Lift Heavy Weights, Very Slow with Minimal Reps - and never hold your breath.
Several years ago I learned about Meditation and the importance of slowing down and focusing on your breath.
Recently I decided to combine my Weightlifting Workouts (and stretching sessions) with Meditation! It's amazing how focused and connected you will become to your breath and muscles.
I don't have a one size fits all recommendation, but here are some general concepts to follow:
Best to find in a quiet and private location
Select a Meditation from an App or YouTube with similar length of your workout (30-60min). While the meditation may recommend sitting or closing your eyes, you don't have to - as long as the music is calming, slow and the topic is generally focused on the breath.
Determine your workout exercises in advance and write them down
Select appropriate weights to allow you to move slow (6-9 seconds in each direction). NOTE: Works well with body-weight exercises as well.
Bring any weights or equipment in a central location
Start the Meditation session and allow yourself to be still for a few moments. Focus on your breath and bring attention to your body and specifically your muscles.
Then focus on staying in the moment as you slowly start your first exercise. Again, each Rep and each direction of the Rep should be purposeful, slow and should include an intense focus on your in and out breaths. When possible close your eyes.
Switch between exercises slowly staying with the Meditation.
Allow yourself a few minutes at the end to again be still and close out the Meditation along with the session you selected.
It's a nice change of pace and well … variety is the spice of life (and exercise)! Here's to your strength both of body and mind.