It depends what you want to achieve with your blog. Are you looking to chart your experiences, or educate people? It may well be that it's a bit of both. Also, who are your target audience? Think about whether you are tailoring things to other diabetics, or to non diabetics, where more explanation may be needed. For instance, if you wrote 'Went for my HBA1C today. Hoping for 6.5 or lower', that would be fine for other diabetics. However, you might as well be speaking Martian to many non diabetics.
Next you need to decide how much time you are going to dedicate this, and how brave you want to be. You could post every blood sugar result you get, what you are happy/unhappy with and how you will move forwards. You may not be comfortable with this, so you might just post about unusual results.
The bottom line is, you can post pretty much anything you want, but try and think about who you are trying to reach, and tailor it to fit that audience.
