Hannah, my daughter, bought me this lovely notebook cover recently. An A5 notebook like my Leuchtturm 1917 fits inside just perfectly. I use a Lami Safari fountain pen, which stays clipped to the back cover, for the majority of my writing. Although I have been using Sharpie fine point pens to fill in my habit tracker, nutrition tracker, and to mark the 4 different times of my day.
In my journal: I keep my monthly habit and goal tracker on a piece of dotted paper so that I can fill in the boxes as I move through the month.
My daily pages always include the date, day, weather, and nutrition tracker. I don’t count calories, I just fill in a box for each serving I eat. I have goals, but if I overeat on one category that is just fine. I refuse to stress too much about weight. I’ve been down that road a time or two and have decided it is not worth it. Not at all worth it. Then I just jot down (usually as a bullet point) what I did as I move through the day.