It can make your work seem sloppy if you use signposting words in the wrong contexts. Avoid the temptation to dot signposting words throughout your text at random. Think carefully about the link between two paragraphs or phrases, and choose a word that effectively conveys that link. For example, 'however' should indicate that you are adding something to the previous point. Another example is 'consequently' - do not use it if the idea that follows is not truly a consequence of the previous one.
Remember: precise and concise language helps you to communicate accurately and effectively with you reader.
You can signpost your reader back to things you have already covered (e.g. 'as discussed') as a reminder and summary to the reader. This should happen at the end of paragraphs, to highlight the point that you have made and its relevance to your essay question. You should also use retrospective signposting in your conclusion.
In order to understand the causes of the London Riots, it would be useful to apply sociological theories...
The reader realises in advance that the writer is going to be using some theories to explore the causes of the London Riots.
Another aspect of Hardy's portrayal of Tess is...
This reminds the reader that at least one aspect has already been discussed, and another is about to be revealed.