We were fitted with ours by a thoracic surgeon who specializes in esophageal strictures amongst other things. We use a 46 and so far it’s been a life saver.
We insert up to the white 35 mark as directed by the doctor. I coat the dilator with KY jelly. My husband takes a few deep breaths and I lay it on his tongue and direct him to swallow. As soon as he swallows I know it’s going in correctly and I ease it down quickly until the 35 is at his lip. As it’s going down I coach him to breathe around it, very important not to hold your breath! Then I count to 10 and pull it out. The whole thing takes 20 seconds and the swallow has to be timed exactly right to when I start easing it down. You should not have to push!
You may want to look at a product on Amazon called Healios, it’s made by a doctor and provides nutrients to the esophagus for people who’ve had radiation. My husband finds it soothing before or after dialsting.
Hope this helps