Though it has been said before it is certainly worth repeating, Flight Sim is great. Choose any jet in there and fly as many approaches as you can get your hands on. Fly them to minimums and throw some increasing x-winds and turbulence as you get more proficient- try to have a good profile and stay on speed etc. Get familiar with using VDPs in the non-precisions as well.

I have more time on Flight Sim than I do total time. I started using it when I was working on my instrument rating and my instructor could tell right away.