Ok, let me do this a little simpler, first off I suggest a simple airport, try McKinney Municipal (KTKI) in McKinney Texas. LONG runway, you can practice with any aircraft there. Tune the runway 17 ILS frequency in NAV1 while at the end of runway 17 preparing for take off (17 is the default runway). The horizontal bar should move to the top of the guage or the attitude indicator, depending on the aircraft you use.
Take off, fly the pattern, request a Touch and Go landing. Fly the plane south of the airport, use the VASI or PAPI lights (those are the red and white lights to the left of the runway) to line up, when you have two red and two white lights, turn and line up with the runway, keep there two red and two white lights and you are perfectly on a visual glidescope. The ILS beams on your gauge will show a perfect approach if you folllow a visual.
Now, the autopilots in the airliners and commuters are MUCHO BETTER at following an ILS then a Cessna is. However, the whole thing is screwed, and you will need to pretty much put it on the ILS yourself before the A/P wil take over and fly it. Turning it on at a random altitude and heading will usually result in hell going loose, since the A/P will oscilate the plane all over trying to capture the course (I decided to see if this was the truth, flew it in a real Cessna 172 at KTKI, which is my home airport. by the way, ILS isnt standard in a 172, a damn A/P isnt standard lol. The autopilot preformed a smooth turn to 176 (runway heading) descded, captured the glidescope, and flew the approach, no problemo). Notice, you should NEVER let the plane fly the full approach to the ground, it is bad for you, and it is NEVER done in reality. If you cannot see the runway by decision height, go around, DO NOT FLY THE APPROACH. Heavies sometimes use the APPR feature even in good weather, since they are hard to move around anyways. If you use the approach feature in Flight Simulator ALL the way to the runway to the ground, you will hit and you WILL hit very hard. (for some reason, M$ took out the feature which was in 95 that caused the airplanes to flare at the last second, gave a VERY smooth landing).
So, simply, tune the ILS, get the bars in the center of the gauge, and fly a normal approach, or get the bars in the center, let the A/P fly the approach to decision height, and you land it.
Once again, DO NOT let the A/P fly the approach all the way to the ground, it will hit still desceding in an approach, and will break the landing gear off most realistic planes and leave you surrounded with fire trucks. Good luck, have fun, and I hope this helped!
