Using buildings, people, and other details to will make your model railroad come alive. Even though this involves quite a bit of work, it can be one of the most enjoyable parts of building a model railroad. Making buildings to use on your model railway can be done by buying an already made plastic form, getting a plastic model kit, or getting a craftsman kit that lets you make a more detailed design. You can also find pieces like doors and windows and building surfaces that look like bricks, rocks, and just about anything else you can imagine.
2 Cheaper building kits come with details already designed on them. More expensive kits, however, let you put the pieces of the building together yourself. Pre-made kits come painted, but can be painted again if your wish, while the kits you craft yourself must be painted by you. Regardless of whether you decide to use a simple plastic model or a complex craftsman design, you need to paint all of the pieces before you start putting them together. If you are not sure what exactly the structure will look like or where certain pieces go, you can put the pieces together without gluing them to help you envision the final product better. Be careful to not get paint in joints where glue will be put.
If your goal is to make the buildings look real, you will need to make them look at least slightly weathered by the elements. Consider how different materials are affected by the aging process and use those ideas when painting them. Not just your buildings but also your train cars themselves need to look weathered. If possible, try to use the same paints on your locomotive, train cars, and buildings.
4 If you can't use the same paint for some reason, at least try to use paints that match up well. Paint with a matte finish works best to give objects a weathered look. You can also use matte finish paint to show rust and wind-bleaching. Since not all buildings are weathered at the same rate or in the same way, use different techniques on each building and train car so that they all look weathered in a unique way. You can get lots of good ideas by visiting a train yard or looking at photos of one. Take notice of the rust stains and how the different buildings, trains cars, and even the tracks themselves have been affected by the elements. Also, be aware of where soot and dust collects in the largest amounts.
Sources for the slides: http://www.youtube.com/user/modeltrainsrailroads http://ezinearticles.com/?Model-Railroad-Buildings---Suggestions-ForStructures&id=1805975