Sections ~ or signatures as some people call them  ~ can be individually sewn with any number of holes. Frequently an odd number of holes is used ~ but any number greater than two works with the method shown below.
The pictures illustrated here ~ unusually ~ treat each section singly. Normally when making a multi section book the sections are linked together in a variety of ways ~ which makes things a little more complicated. I have used red thread in the topmost picture and yellow in illustrations below .
The thread here has been unwound from a small reel. It has preserved some of it coil. This can be straightened out by running it across the edge of a folder ~ or better still by running the thread around a beeswax block  The thread is less likely to cause tangles if it is straightened and stiffened with wax. For some reason I did not do it on this occasion.
If you are wondering about the little leather strip there is an explanation .
Tap the sections down to ensure that all the holes are aligned ~ as they were when the awl was being used. Keep a firm grip on the leather strip and from the valley of the hinge pass the needle through one of the near-central holes. It helps to leave five or ten cm of thread for knot tying ~ later.
From now on ~ for a while ~ work the needle in ~ or out ~ of the next adjacent hole ~ moving in the same direction until you reach the end. At that stage turn round and work ~ in and out ~ until you reach the first hole you started with. Skip over this hole ~ making a double length loop. Then continue in and out until you are about to go through the lasthole - which was also the first ~ from the outside to the inside. At this stage ~ carefully ~ pass the needle onto the other side of the loop ~ illustrated in the two pictures, below.
Tie a reef knot using the two threads ~ making sure that they trap the loop of thread between them. The next picture shows the first half of the reef knot about to be pulled tight.
Once the reef not is tied the ends can be snipped off neatly ~ job done.