Basic advice - front cog won't shift

[Dan_1981]

Guy

In need of some very basic maintenance help.

Out on a ride today and could here the chain catching on the front deraileur, was getting gradually worse, so stopped to have a poke at it, set off again and front cog now won't shift up or down.

Is there a method to "resetting it" to its optimum position / setting and what / how do I need to do this?

TIA

[Paul Drawmer]

Sheldon Brown has a lot of good info:
Try this:
http://sheldonbrown.com/derailer-adjustment.html