In testing clays and making glazes, you must
have a notebook of some kind. Each test you do
needs to be recorded. Your results, your
thoughts, everything. It can take a week or more
for 1 test to be complete and if you don't write
down what you did or what you are intending to
do you will probably forget, especially if you
have several test going at one time. Get in the
habit of writing everything down. Photo's are
nice too. I also number my test for easy
reference. Here is a picture of my clay
testing/recipe notebook.