Posted: 12/08/2014 at 11:44
first remove the green plastic tie thing so that the plant can spread itself out and you can get in to see what needs doing,
remove the canes that have had flowers and fruit on this year the to the ground as well as any dead or old canes (a tip is the older the cane the darker brown the bark)
as its in a pot I would leave the suckers (these are new plants trying to form after all) you can transplant them out in spring if you want new plants.
you might only have three or four new canes left after the pruning, after you've finished pruning give a good water and a fertilize, I would say a nitrogen rich one as you want shoots and leaves as the fruiting is over.
it might take a year or two of this pruning regime for it to settle down and produce good fruits, plus rasps don't like being grown in containers as they are hungry thirsty plants