Here are my trusty and a bit rusted crimp pliers. I generally use 2mm crimps with these pliers.
You can see that there are two sections to these pliers, one for making a dent in the crimp bead, and the second for folding it in half.
Dent in the Back Section
You use the back section to put the dent into the crimp bead and this is done first.
Here is another view showing the crimp is squeezed in the back part of the pliers to start. Notice that the dent goes between the cord so that one piece of cord is trapped on either side of the crimp bead. This is important.
Using the Front Section
Next move the crimp bead to the front section of the pliers where you will bend along the dent to completely trap the bead wire in the crimp bead.
Detail of the Squeeze
Once you have completely squeezed your crimp bead you can then trim the extra length on the short side.