you're doing it wrong

When you build a structure with visible supports, make sure that the supports actually connect to and support something. This saloon model was entered in the model contest at the MWR convention in Waupaca last April. If you look closely at the image, you'll see that the support poles at the far right and far left on the porch don't actually support the roof over it. A mistake like this takes points off construction, which is the largest emphasis in NMRA's AP judging criteria, unless you can show documentary proof that the supports on the prototype structure also didn't actually support the roof.

I saw an ad on television recently that touted the importance of a good foundation. Just like the prototype, your model structures could be quickly and easily improved with a good foundation too. Look around at the buildings in your neighborhood; the foundations are usually visible as a narrow strip of concrete below the wall that makes up the side of a building. Sometimes the foundation is painted in the same color as the rest of the wall, sometimes it's left bare. Whatever its color, a quick box of styrene strip material will easily simulate such a foundation. If you don't add a foundation, you could end up with something like this image where the structure appears to be floating above the ground.

When you install a long bridge on your layout, be sure that there's enough room under the bridge to support the ends of each of the bridge girders. This bridge has no hope of staying up on the prototype because of all the unsupported girders.

When you're assembling a kit structure, spend a little extra time to make sure that all the parts fit snugly, even going so far as to fill, sand and paint over any gaps that result from assembly. A seam like this one will definitely not help you in merit award judging.