Begin by standing on a comfortable surface, where you have plenty of room at each side. With a _5 lb potato bag_ in each hand, extend your arms straight out from your sides and hold them there as long as you can. Try to reach a full minute, and then relax.
Each day you will find that you can hold this position for just a bit longer.
After a couple of weeks, move up to a _10 lb potato bags_. Then try 50 lb bags and eventually move on to where you can try and lift _100 lb bags_ in each hand and hold your arms straight for more than a full minute. (I am at this level).
After you feel confident at this level, start putting a potato in each bag. Enjoy.... ATB Dougie.