The l2tabu tutorial (mentioned in online introductions) is undoubtedly a good read.
However, it’s always difficult to remember the things you should not do, when there are so many things to remember that you really must do: some automation is useful….
The nicely-named nag allows you to apply a configurable set of checks to your document, as you run it through LaTeX; you get messages like:
(the package provides a demo file which contains most of the sorts of errors you might make — the example is one of them). While l2tabu and nag alert you to possible programming errors, you should not forget that they are merely commenting on style; don’t assume that a nag error is going to damn your code — rather, note the issue and try to train your fingers not to do the same “next time”.Package nag Warning: Command \bf is an old LaTeX 2.09 command. (nag) Use \bfseries or \textbf instead on input line 30.
The lacheck program analyses your source and comments on it; its view of what is “bad” is very subjective (the documentation says), but it can be useful.
There’s also a web site TeXidate which will do a static analysis of your document (unfortunately, you have to paste your document source into a text window). The site doesn’t seem as comprehensive as nag, but it allows you to download its script, which you can then juggle with to make it more draconian.
This answer last edited: 2012-10-09