Automated BP cuff
You can buy decent automated arm cuffs at the pharmacy (arm not wrist) & that's a good place to start. You'll be given a reading with 2 #'s: 1st, higher # is called systolic bp, and 2nd, lower number is the diastolic. An ex. Of how you write it would be: 120/70. Check your BP while comfortable at rest. Record 1-2x/day at diff times of day, or as per your doc's instruction.