Kneading
When flour, water, salt, and yeast have been mixed together, before the dough is left to rise, it should be kneaded to maximise gluten formation. There are a number of techniques for kneading: I recommend using a stand mixer fitted with a dough hook. Whatever sort of bread you are making, the procedure is generally the same: mix on low speed until the ingredients are mixed together, then turn to medium speed for five minutes.
If you don't have a mixer, you should find the following technique successful. Start with the ingredients in a bowl and mix with a wooden spoon until all the flour is wet. Tip the mixture onto an unfloured work surface - it is too easy to keep adding flour to stop the dough sticking, and this will change the character of your bread. At this point, the dough will be an amorphous sticky mess, but bear with me and you will feel it transform. Pull the dough into an elongated sausage shape and slap one end down hard away from your body onto the worktop, allowing it to stretch out. Fold the end nearest to you over the far end, reshape a little, then repeat the process by picking the dough up from the nearest end. After about five minutes of slapping, stretching, and folding, the dough will hold together easily and feel smooth and silky.
At this point, whether you have kneaded with a machine or by hand, you should be able to check that the gluten in the dough is properly developed by using the "Windowpane test". To do this, you pull off a piece of dough about as big as a walnut shell and gently pull and stretch it out into a thin membrane. If you can stretch it thin enough to see light through without it tearing, then it has been kneaded enough. If it tears, knead it for another minute, then test again.