You can't be a falconer without being able to tie your bird to a block or your glove. The good news is you only need to learn one - "the falconer's knot"
To learn how to tie the knot one handy tip is to practise with a hook or a nail on a piece of wood. This way as you can see easily what you are doing, the hook won't flap its wings or try to claw you with it's talons and you won't have the stress of losing your bird.
You only use one hand to tie the knot, which makes it looks more complicated than it really is. Once you've got the hang of it, it's pretty easy.
Here is my step-by-step guide, I hope it comes in useful.
Fold the leash as shown then place your forefinger and middle finger around the leash as if they were a pair of scissors. Hold the long end of the leash with your thumb.
Hook your thumb behind the short end of the leash and pull it in front of the long end of the leash.
Now with your forefinger "flip" the short end of your leash around the back to create a loop.
Fold the short-end to make a second loop and pull this loop through the first.
Now take the loose short end through the second loop.
And that's it you've successfully tied a falconer's knot.
The reason it's so useful is that it's secure but very easy to untie - you simply reverse step 5 and pull and it all comes undone!