Can anyone provide a link to a step by step guide on TrueType hinting? I don't find the Fontlab manual very user friendly on that point.
There is none that I know of.
There are quite a few resources on the Microsoft Typography site, specifically associated with Visual TrueType (VTT).
See the Practical TrueType Hinting PDF for some FontLab-specific examples.
There are a lot of things you can do to maximise FontLab's autohinting without getting into manual tweaking of hints. See Notes on Hinting with FontLab. Adam Twardoch wrote up a much more detailed follow-on: Autohinting with FontLab Studio 5. You may also want to try avoiding FL's hinting altogether with ttfautohint.