Something I just thought about that I find helps, sometimes significantly for some dogs (puppies especially with first grooms), is to let them sniff things! It sounds simple but tools, brushes, dryers, whatever they seem a little scared and curious of. Of course keep safety in mine because I have seen dogs go straight for the point of my scissors trying to check it out. I usually point it down and away, let them sniff the handle. Even the cotton balls I let them sniff. Dogs experience so much with their hightened sense of smell, so sometimes just a little sniff helps them realize it's not a scary object. Especially the dryer as you slowly turn the dryer on. I have seen lots of people in my work places try and rush the dogs through things and sometimes all they need is for you to slow down and honestly? I find myself much calmer when I have to slow down for nervous dogs. Lots of room for deep breaths if things get frustrating.