The whole protein looks like this, the ligand is shown in red.
If you draw the protein with its van der Waals surface, you notice that there is a small opening which is probably the place where the ligand entered the binding pocket.
Apparently the receptor closed again and the molecule is trapped in there.
If you eat away some of the outer amino acids, you can take a better look at the binding pocket.
Or at a semi transparent binding pocket:
Remove some more amino acids that are in the way and it'll look like this.
How do you create those picutres in pymol?
First you select one chain (the fact that there are four chains is just because that's how it crystallizes):
select cha, chain a
If you go for "preset pretty", you can see the ligand and select it. Call it lig. Then you can modify it, give it double bonds, show it as ball and stick model, ...
For the main protein you may want to select the different secondary structures:
select helix, ss h and cha2
select sheet, ss s and cha2
select loop, cha2 and not (ss h or ss s)
Then you can color those the way you want.
If you want a surface, it makes sense to duplicate that chain a and show the duplicate as a surface.
If you want to select the binding pocket, go for:
select pocket, (lig around 5)
Then you can erase some of the amino acids that are in the way.
Of course after doing all this, you have to play around with colors, perspectives and rendering methods.