Lay each slice of bacon on a chopping board and, using the back of a knife, scrape along the bacon to stretch it out and make it thinner. Weave the stretched bacon together to make a lattice by laying half the strips horizontally, then folding every other one back and laying a strip of bacon down vertically. Fold forward the strips bent back then fold back the alternate rashers, laying down another strip vertically. Repeat with the remaining rashers. Lift the turkey breast onto the bacon lattice, skin-side down, and fold it around, bringing the turkey back into a breast shape. Slip kitchen string under the turkey at the middle and tie to secure. Tie the rest of the turkey up at intervals along the length to make a neat shape. Weigh the whole joint then calculate the cooking time based on 20 minutes per 500g.