In a post from 2013, I wrote about occlusive exercises. I am still not a heavy user of them, but they can help a singer (and once in a while me) to calm the heck down when overdoing.
I do not like the ubiquitous straw. I have seen huge discussion threads about lengths, diameters, materials, blowing bubbles in water, how deep the water should be, and other details. They just aren’t necessary! Using a prop like that takes us too far away from singing and puts us somewhere else. I think it is worth the effort to figure out how to use your own body. It’s not hard.
I wrote before that I preferred the “V”, or in IPA /v/. I have found one I like even more, which is very similar – the “Spanish B” /β/. If you feel compelled to use an occlusive, the /β/ has a unique advantage. In addition to the voiced sound, you will feel and hear the passage of air at the lips. Trying to keep the pitch of the voice steady and also keep the sound and sensation of the passing air steady is quite a sport. While sustaining that sound, I keep my posture tall, but relaxed and steady, and don’t let my rib cage suddenly collapse. Do this in the lower and middle range as I suggested in the previous post.
Someone who honks or blows tons of air or valves hard in the larynx can feel a very different kind of voicing with this exercise. It can be a good gentle start to a session, even if it does nothing more than help you calm the heck down.