STEP 1: Start by deciding on a size or “scale”. 
            Think big for under the tree. 
               (See comparison of train sizes and scales) 

• Avoid small size trains. Unless you set up a 2 or 3 foot tall Christmas tree on a table the most common size model train (HO Scale) is too small. The relatively low cost of HO scale makes these sets an attractive choice, but at about 1 1/2 inch in height they will get lost under a 5 to 7 ft tree.  HO scale also doesn't work that well when set up on the floor or carpet.  N scale which is half the size of HO cannot operate on the floor at all.

• Lionel O gauge trains are a good choice for 6-7 ft trees in a small or moderately sized room.  A traditional set with a sturdy metal engine that puffs smoke and whistles is a great choice and  includes a minimum of a 3 foot circle of track. 

• On30 sets (either a regular train or the popular back and forth Street car sets )are perfectly sized for Christmas villages. These big O gauge cars running on HO track take up almost no space at all in your village.

• Large Scale trains really standout under the tree. Twice the size of Lionel and 8 times the bulk they’re ideal for under a Christmas Tree of 7 feet or more. Keep in mind that the minimum circle of large scale track is 4 .5  feet but these trains really run better in a 5 to 8 foot space.

• If you have small children or pets the sturdier and heavier Lionel or large scale trains are more likely to withstand their interest and attention. 

STEP 2: Find the best value in a Christmas train set

• Buy a complete beginner set package. You’ll have everything you need to set up and run the train and you will save 50 to 80% over the cost of purchasing all the separate pieces. 

• Think about future expansion or replacement parts. You may need to replace a lost or broken piece next Christmas or decide to add on or start a year round model railroad. So, avoid picking up an “orphan” set made by a toy manufacturer or other company that doesn’t offer a complete line of model trains. Your safest bet is to stick to hobby store quality, name brand sets in one of the established scales: G (or Large Scale), O (Lionel), HO or N. And, try to purchase your train set from a retailer that offers a full selection of parts to go with it. 

• Get a set with roadbed style track. It’s easier to set up and put away. Plus it doesn’t require mounting on a board and can be set up on a floor or a carpet. 

• Consider the style or theme of your train.  Festively decorated Christmas trains or special holiday themed trains like the Polar Express are obvious choices for running around the tree.  As an alternative, many choose to run a regular style train.  The traditional Lionel set with a metal engine that smokes and whistles is a popular choice rich with nostalgia.  Plus, regular trains with standard road names can be used all year round!

STEP 3: Set up for smooth trouble free operations.   Your Christmas train display can be as simple or elaborate as you wish to make it. Most families enjoy the nostalgia of a train circling the tree on a quick to set up loop of track. Many also get into adding a few operating accessories or illuminated Christmas village buildings to their display. 

A few Christmas train engineers construct elaborate platforms full of festive winter scenery. Whichever approach you choose before you begin to set up your Christmas train consider the following:

• Trains run best when the track is set up on a smooth level surface. The size of your train dictates the amount of preparation required. Large scale and Lionel trains with roadbed style track will operate well on just about any level surface. (Avoid using non-roadbed track on carpeting as the carpet fibers can get caught in the wheel bearings.) If you are using the smaller HO scale it is very important to set the track up properly and take some time to prepare the surface. Although an HO train can operate when the track is simply set up on the floor or carpet, for hassle free around the tree operation your best bet is to attach the roadbed track permanently to a piece of plywood and set the tree stand on the middle of the board.

• Layout and connect the track properly. You can do this before the tree is set up or after. (I do it after but often find myself having to crawl under the tree to make a  connection.) Pay attention to the “geometry” of the track. Determine the number of sections of curved track that make a full circle of your track. Note where your power controller will be and place your power terminal track connector at that location in your track layout.  If you need a larger circle or oval to fit around your tree you can easily lengthen or widen your track layout. First assemble 2 half circles or 4 quarter circles. Then add an equal number of straight track sections in between each side of the half or quarter circles until you have the size you need.  Examine the track connections after you assemble the sections.  Each piece should fit squarely against each other and the joints should be flush and smooth. 

• Once your layout is set connect the power and do a slow test run with the engine to check for proper clearances.  Make adjustments by trimming branches or moving ornaments as needed.  Then set the rest of the cars on the track making sure that the couplers are connected properly.  If the couplers don’t hold the cars together securely make adjustments or replace them. (You may be able to make a temporary fix by using a plastic wire tie to secure them.) 

Now you’re ready to put on your engineer’s cap, blow the whistle and begin your run to the North Pole.  I hope these tips help you enjoy running your trains at Christmas as much as I do! You might even get a bit carried away (and if your family is as tolerant as mine) find yourself setting up track right across the living room.  Last Christmas I worked it out so my Polar Express circled the Christmas tree traveled across the room in front of the hearth, looped around a table and chair or two then ran back to the tree.  
Whether your Christmas train travels around simple circle or winds its way all over the house your new train should provide many hours of trouble free operation. To assure that it does, here are couple of quick tips for the maintenance of your train:  

1. If the train begins to stutter or stop while running clean the track sections with a track cleaning eraser or very fine sandpaper…DO NOT USE STEEL WOOL. Do the same for the metal wheels or power pickups on the loco.  

2. Examine the car wheels and axles and remove any tree tinsel.   It's best to not use tinsel on your tree if you are running trains around it. 

3. Use oil very sparingly. Generally new model trains require only very occasional oiling of the wheel bearing or gears. Consult the manual that came with your train.  If you do oil the train use a very light oil applying just a small drop or two.