Weight – Try to use a reliable weighing scales, one which would give the same reading if you were to weigh yourself a few times over a short time period.
Pwyso - Ceisiwch ddefnyddio clorian d d ibynadwy, un a fyddai'n rhoi'r un wybodaeth pe byddech chi'n pwyso'ch hun ychydig o weithiau dros gyfnod byr.