I have a relion bp monitor with cuff that adjusts for standard to large. i am going crazy be cause not sure if i am fitting it right + at heart level?

BP monitor: Sit in a chair with an armrest; wrap the cuff snugly on your upper arm with the sensor over the front surface of the elbow or slightly above it and rest your arm on the arm rest. It might be easier for someone else to wrap the cuff properly around your upper arm so that it's snug and properly fitted to your arm.

No need to fret: The cuff should be wide enough to cover 2/3rds of upper arm. It should be long enough to wrap completely around arm with about 2 inches of overlap.It should be snug but not tight. If it slides up & down arm, too loose. If you can't get a finger under the cuff, too tight. Don't worry about level of heart, just sit or lie down &try to be relaxed. Sitting at kitchen table with arm at rest is good.