Start by activating the yeast. Put the warm water into a cup and add the yeast. Slowly the water will become foamy as the yeast starts to become active.
Put the flour in a large bowl and mix in the salt. Make a little hollow in the middle, pour in the dissolved yeast, and stir it in until it slowly comes together. Add in some of the cool water until it becomes a stiff dough. Cover the bowl with a cling wrap and set it aside for 30 minutes, if possible in a warm place.
After 30 minutes, turn the dough onto a lightly floured surface. Shape it into rectangles and fold it into thirds. Turn it over and repeat the process.
Oil a big bowl and place the dough in it. Cover the bowl with cling wrap and let it rise for an hour or two. Leave the bowl in a warm place to encourage yeast activity. The dough will double in size during this time.
Put the dough on a floured surface and divide it into four equal parts. Shape them into long baguettes, put a light coating of oil on top, cover with a flour-dusted tea towel and cling wrap, and let them rise for half an hour to 45 minutes.
Preheat the oven to 450°F and place a water pan on the bottom rack.
Uncover and transfer the dough to a buttered baking sheet and make four light slashes on each piece with a knife. Dust lightly with flour.
Bake for half an hour or 45 minutes until browned and crusty.