Dont be scared to bear away. Bear off and get up to speed, then head back up wind once you are going flat out. As mentioned before, rig big, full downhaul, long harness lines, straps out and back, sheet on, bear away with foot steering tilting board away, keep down pressure on the back foot. Get the mast base in the right place, 3cm will make it feel like a different board. Sail lots. Sail in rough water. Sail diamonds rather than reaching back and forth, ie sail 120 to 135 degrees downwind, then sail upwind the gybe, then downwind, then upwind, this will get you used to getting up to speed before trying to sail up wind. If someone is passing you, bear off and sheet on. Pump like crazy, dont let them pass. If you havent sailed like this yet, then give it a try. If you can sail like this for 10 minutes first time, go back to the beach and rig up with an extra m of sail. First time you sail with a big enough sail you just wont last. Dont worry, after a few times you will get it, before long the 9.7 feels like the old 7.8, then when its howling the 7.8 will feel like wave gear. The pros can sail like that all day, but us mere mortals cant. but we can manage a few runs. Gives us all something to aim for. Good luck and sail fast