6.0 is normal for non-diabetics. An A1c is the blood test that tells your doc what your sugar readings (even without a meter reading) have been for the past three months. An 8.6 is extremely high and reason for concern. 6.3 - 6.9 is reasonable but requires watching.
There is a regimen that diabetics are supposed to follow. You are supposed to take a meter reading before and after breakfast. Then depending on what your doctor wants you to do, at least two to three more readings during the day.
Being me, of course I don't do it that way. I know my body, and know right away if my sugar is climbing. And like all diabetics can tell instantly if we are crashing. If the sugar goes too high, we can slip into a coma. If it crashes, then we can have a seizure. So if I am having a good week, I may not test my sugar at all. Or if I am having a bad day, I may check it several times until I get a reading I like. It i a toss up as to which is worse. Crashing or climbing too high. If you are crashing, you feel shaky inside, then shakey all over, start to sweat, breath with shallow breaths, get very weak. That person needs to get sugar into them right away. Or:
Like me right now. I checked my sugar. Not feeling good. Meter is reading 219. WAY TO HIGH. I will take a glipazide. Insulin in pill form. For those on the needle, they need to get a shot of insulin into them to get it down. A reading of 90 - 110 is normal.
This all becomes a way of life. With insulin and diet, diabetes can be successfully managed.
More info than you need or want?