Track is one of the first stumbling blocks for modelers looking at 16mm scale. But fear not, I too have faced this dilemma and have overcome it with the following scheme.

First of all you need some rail for you track. Unfortunately it is rather expensive to buy new, however I found that old Triang OO track was, well, ever so slightly overscale. About 3x so! And it's dirt cheap. So get yourself down to your local model shop and buy up large: this stuff goes for a dime Then simply remove the rail from the track.

   

These are also easy. Find a 1x1 inch ground treated garden stake and take to it with a band saw. One with a moveable guide rail is best Trim them all to size (mine about about 10x10x60mm) and then stain them (if needed).

   

How does one attach steel rails to wooden sleepers? With solder of course! And how does solder stick to wood? Well you make use of little brass tacks and a bit of flux.

To hammer in the tacks in the right place, I made a small jig. Simply place tacks in the gaps and hammer in.

   

Once that is done tin the heads of the tacks. This makes the soldering later on much easier!

A jig helps for this section. I used another section of track to position the sleepers, but guessing works too. Lay out your sleepers, then place the first rail. Heat each joint and add solder to make the joint. Allow to call and move on.

Once the first row is done you can then move onto the second rail. For this I have a jig to make sure the track is the proper width apart. This is highly recommended! Do the second rail joint by joint, much like the first rail.

   

And when you're all done, you'll be left with a section of track that looks just fine in the garden, suitable burried, er, ballasted.