Nocking the arrow
Before you shoot, you have to nock the arrow. It consist of both setting the arrow to the bow itself, and locking the bowstring into the nock groove (or rather the groove on the bowstring), .
The locking part is harder. When shooting quickly, you have to be able to do it with minimum of moves, confidently and without looking, because your sight is always concentrated on the target. This part of whole shot is most risky one in my opinion; it is quite awkward if you draw you arrow in a lightning-fast fashion, put it to the bow with hudered-times-perfected moves, and then spend several seconds by trying to hit the bowstring by a nock.
Generally it an be said that the fastest ways of nocking the arrow are those where at the begining you hold arrow with two or three fingers by its nock. It does not make problems if you draw your arrow from a controlled place (a quiver for example), but it IS problem if you draw it from anywhere else (for example if you grab the arrow from ground, or you catch it when someone threw it to you). In these cases you can do nothing else than use slower but more reliable ways (pumping).
As soon as the arrow is nocked successfully, you back (string) hand will end on the bowstring in certain position. The position is determined mostly by how you hold the arrow at the begining, and to which side of the bow you put it. If such a position is not suitable for you for drawing the string, you first have to change your grip, which unnecessarilly spends time (not some much sometimes, but a little bit always). If you don't want to lose the time, it is neccessary to do everything in a way so the hand ends you in the exact position you want to use for string drawing. Possibilities of holding the arrow.
General principles
Whatever way of nocking you use, it is necessary that the nock locks on the string immediatelly and without looking. To ensure this, you have to twist the arrow in its long axis correctly, just before you start to push the nock against the string. This is done by rolling.
There is a useful mechanism that I call the rail principle, which is often used during nocking. The rail is something that guides moving thing to the right place - for example your hand to the end of arrow, or the arrow nock to the bowstring. Thanks to the rail principle you ensure the right motion without looking at your hands, and thus also a reliable nocking. In every way of nocking, there is always something that slides on something else, leans etc. Example - when nocking by a push from the inside, you start by leaning the arrow on the bowstring. The bowstring then works as a rail that guides the arrow when pushing forward. After the bowstring skips below your thumb, the sides of thamb and index finger then work as a rail guiding the bostring to the arrow nock.
Ways of nocking the arrow
I have divided the ways of nocking into two categories. Techniques with exact hold are extremly fast, but they require to hold the arrow in an exact way in the begining (always by the nock). Techniques with a free hold are slower and consist or more moves, but they can settle with not perfect holding. If you draw arrows from a controlled source, you usually have the possibility to grab them in the exact way - and than it would be pity not to use the superfast technique with exact hold. On the other side i you just grabed your arrow from anywhere, you don't hold it perfectly, but techniques with a free hold still allow you to shoot quite quickly.
One last notification - the names of techniques are my own, because I don't know of any generally used terms.
Techniques with exact hold
- Nocking by a push - fast and quite reliable, my favourite one. But it requires a specific starting hold.
- Nocking by a pull - fastest, but in my oppinion the hardest to master.
- Nocking by taking around - quite fast and also reliable variant, something between the push and pull.
Techniques with a free hold
- Nocking by pumping - slower way with more steps, which is al the same the most reliable way of nocking that I know about. If arrows spill in your hand, or you don't have them in perfect position, pumping will save you.