It is a very simple process. I took three readings and they were all different.
It jumps around all over the place, and three readings in succession after sitting for 5 minutes prior is the suggested way to go.
I'm a classic white coat syndrome sufferer, so never really take a lot of notice if it ever gets taken be a professional at the surgery, or if I used the machine in the surgery.
My doc wanted me to go on meds, but I convinced her I'll go away, have a look at a few things [namely my booze consumption] and report back. I've had two occasions with a 24 ambulator[a device wore for 24hrs taking a reading every hour] over the years, which, although a bit inconvenient during the day, was very interesting to see the results. Interesting to see what happened to it at night, and also when a did a session on the turbo......on purpose - 'through the roof' comes to mind lol
I have a couple of monitors at home now, and I go through spells where I take regular readings and spells where ICBA. I've been borderline hypertensive for a long time.
Well worth keeping an eye on it though.
There is a reason why it's called the silent killer.