A beautiful line begins with a well-held pen.
Keep the small vent hole facing upwards, and hold the pen lightly, with a relaxed hand. Try to keep the nib at a 30 to 40 degree angle to the paper. Turn the paper itself to find the most comfortable position for your hand. I shall show this initially for right-handed writers, with the left-handed version at the end.
Look closely at the very tip of the nib. You will see that it is divided into two tiny points, known as tines. As you press the nib onto the paper, these tines separate. With less pressure applied, the tines separate less and the line is finer. With more pressure applied, the tines separate more, allowing more ink to pass through and creating a thicker line.
Never press forcefully – too much pressure may damage the nib.
When loading your pen with ink, dip only as far as the top of the vent hole, so the hole sits just beneath the surface of the ink. Then drag the nib lightly against the side of the inkpot to remove any excess. A well-loaded nib should be full enough to write smoothly, but not so full that it drips, blobs, or soaks the paper.
For this reason, I recommend placing your practice sheets on the clipboard one at a time. That way, should an enthusiastic blot appear, it will not mark the sheet beneath.