How to Lay Flextrack Curves

Hold the flex track over the curve you need to form, lining it up with the existing piece of track. Check which side is the flexing side and which side is the sliding side by gently bending the track to see which curves and which doesn't. Bend the end of the track to make the curve you are trying to fill.

Trace the outline of the track using a pencil.

Hold a second piece of track or flex track at the end of the curve, if you haven't already installed the track to which the flex track connects. Trace the piece of track onto your model so the end of the lines match up with the flex track you traced earlier.

Join the flex track to your existing train line using a pair of track joiners. Slide the track joiners onto the fixed piece of track, then slide the flex track inside them. Bend the track gently to make sure you have joined the correct edges of the track so that it will bend properly.

Tack the attached end of the flex track -- the one you just attached with joiners -- to the train set surface. Leave the unattached end of the track loose for now.

Bend the flex track into place so that it matches the outline you traced earlier. Tack the loose end of the track into place.

Tack down the middle section of the flex track so that it maintains the curve.

Affix track joiners to the unconnected end of the flex track. Attach the next piece of track and tack it into place.