The roadbed has a small slit down the middle. Cut that through and the stuff bends a lot more easily. You then just have to mark the centerline of the track. I use green contact cement (water-based, no solvents). I've been usung this for most of the foam/rubber/track joins. It does stick instantly, so be careful -- I often use a wax paper separator while I line things up. You might even put some pins in down the centerline and push the first piece of roadbed up to them. I've also used pins into the roadbed to line the track up -- do the cutting and positioning before adding glue. I've also done it using the glue in the ballast to hold the track. Don't glue switches -- they're the pieces most likely to need replacement.