Paddy5, if your bushes are over three years old then they get pruned once in summer and once in winter. In summer, after gathering the fruit, cut the side shoots ( this year's growth) back to 5 leaves. Don't touch the main upward pointing branches , the leaders, unless they are curled up by aphids and then only cut off what you have to to make them healthy. In winter, from Nov. to Mar., cut the leaders, the main upward pointing branches , by a half to a bud pointing the way you want the plant to grow next year. Then, go back to the laterals that you timmed back in the summer, and cut them back again to three buds. As the plant gets older you will have to cut out some of the older leaders to make way for stronger, fitter shoots. But that is it. It's not as complicated as it sounds.
You don't say how many bushes you have, but I have 2 four-year old plants and I've had so many redcurrants this year I left half of them for the birds.