I dont do much to mine give them a mulch in autumn and a tidy! Unless they are not hardy then I protect them over winter.

As Drc mentions, depends whether the ones you've bought are hardy varieties or not - if they're summer bedding ones, you'll have to bring them into the house for the winter, or a slightly heated greenhouse. If they're hardy and in the ground, just leave them alone, don't cut back this year, cut them back (probably in April) when they start showing signs of growth. If they're hardy and in pots, you will need to protect them during the winter regardless - fuchsia is sensitive to cold through its roots, and in a pot outside, they may die.

So true - I lost my 'F dark eyes' last year in a thick stone planter been in there for 2 winters but this winter was the killer