Accordion fold the paper, folding the short edge. Keep the folds relatively small. It does not matter if the folds are not even as the paper will get 'fluffed out' in the next step. Wrap a piece of craft wire around the middle of the folded paper. Carefully make a series of cuts to give a textured edge if required.
To finish, carefully separate the layers of paper and 'fluff' them out. Do not rush this part of the project as the paper is fragile and may tear.
If you are going to make several of these large paper flowers for a party, wedding or other celebration then make them ahead of time but put them to one side before 'fluffing'. This will keep them in top condition before they are used. They are also easier to store in their pre-fluffed state.