Ibanez EWB20 Acoustic Bass - How do I lower the action?

[Distant Cousin]

As title really. the action on it is way WAY too high. Looks like half an inch or so for much of the fret board, so playing anything is far too difficult and not fun at all.
The neck seems to make a sort of convex shape down the length of it, which seems very odd to me.

[RCCollins]

when you say "convex" do you mean backbow?

[Distant Cousin]

I'm not sure what Backbow is, but the neck is curved away from the strings if you look at it from the angle you would play it.