If so, how would I do it.

Yes you can use someone else's glucometer to see what your blood sugar is.
You would have to use a fresh lancet (used for piercing your skin)

You would also have to use one of the test strips that was prescribed with the machine. You just place the strip into the machine, prick your finger and place the blood onto the sensor.

Your blood sugar changes constantly throughout the day. It is obviously going to be much higher after you eat a meal then when you wake up in the morning.

The problem with using someone else's meter is that they have a memory that they may use to guide their medicine use.

To just to be curious about what your blood sugar is, then see if that person agrees to let you use theirs.

Fist you test your blood sugars before meals 1 hour after meals it will only give you an idea of what your B/S are .. only a HA1C will determine if you are a diabetic. if sugar is between 80 and 120 this is the normal any thing over is too high and thing under 80 is too low check with a doctor over this onset diabetes is known for the damage it does to your vital organs Eyes, heart,kiddneys and lungs, if left undetected it can affect these organs before you realize it