It is normal to use a puller for the wiperarms (its in fact in the TIS manual)
You can get special wiperarmpullers for little on ebay
http://www.ebay.com/itm/Windscreen-W...-/231979661274
But the
battery style version will work just as well (as will any small puller that can graps behind the arm)
I have a wiperarm puller but I think I usually grab a small 2 legged puller. Whichever is nearest.