Brio is one of the best toy train sets for young kids because its large wooden shapes are perfect for kids to put together. If you're trying to come up with an interesting track layout to set up your Brio trains, there are a huge number of layouts and designs. You can start with a pen and paper layout, or just try a design and tweak it until it fits.
Most Brio sets will come with enough track to form a basic circle or oval. The circle layout is basic, and you can expand it by adding straight pieces in between parts of the curve to make an oval.
With a cross piece in the center of your train track, you can form a basic figure eight. Alternately, you can use a bridge instead of a cross piece, and place a straight piece under the bridge.
Circle with Sidings
At the top and bottom of a curve, place two switches, and attach another curve to them. This will form a shape that looks a little like an oval with a curve inside it. These create spaces that a train could park in or a second lane for one train to pass another.
Bumpers are placed on dead end tracks so that trains can stop there and not fall off the end of the tracks. Replace part of a straightaway with a stretch, so that the stretch heads toward the center of an oval. Place a bumper at the end of the switch, and you'll have a new layout.
If you can think of ways to combine any or all of the designs and layouts above, feel free to experiment with them. The Brio train system is designed to be flexible and easily assembled. There are also a number of layout designs made by other people which are varied and different. You can find some more ideas for ways to combine these designs at the links under References.