Lissy,
Billy and I have pretty much the same Dx and treatment. You just mix the baking soda, salt and water all together. I premixed mine in the morning and when I was to ill to get out of bed my wife premixed it for me. I did the rinses through out my treatment and I really only had a minor problem with mouth sores. The mucous was a problem for me too. I did the rinses at least four times a day and especially after meals to get left over food and boost, ensure, VHC out of my mouth. It really didn't cut my mucous that much but I'm sure it kept my mouth problems to a minimum.
Stay Strong
Tim