This is arranged for use with a pitched instrument that is an E. In my case, I have a Tibetan singing bowl that may encourage mindfulness due to the attention required to keep the mallet in contact with the side of the bowl. They could also be given a melodic instrument (like a metal tank drum or chime bars) and improvise with As, Es, and Bs (you can give visual cues on the instrument for this if necessary). However, the client could also just listen and breathe, or they could raise their arms up and down with their breathing. With kids you could give imagery about growing tall like a tree and then melting like a snowman, or anything you can think of, especially things they are interested in (tall like a giraffe and small like a mouse for animal lovers) The music is meant to mimic the idea of box breathing, so the rest in the first measure is meant for the client to hold their breath. In the third measure they may run out of breath and do a hold or they may be exhaling till the end. You might use a pulse oximeter to measure their heart rate at the beginning and match your bpm to their heart rate and then slow them down using the ISO principle if you wanted to be super numbers driven. Measure their pulse oximeter at the end to see if your TME had an effect (you want their heart rate to decrease along with the decreasing BPM). Good luck :)