There is a standard answer framework that you should stick to to boost your marks. For an illustration, let's consider a question that came up in 2013 in crime and deviance module - outline and assess Interactionist explanations of crime and deviance.
In the first paragraph, explain key concepts that you see in the question. In your own words, define Interactionism (a sociological theory that emphasises the role of individual in shaping society). Link Interactionism to crime - step-by-step, explain the role of individual interactions in the criminal world, explain the concepts of master status, labelling, self-fulfilling prophecy. After each concept you mention, give a brief definition - you will lose marks otherwise.
Then, bring in statistics to support what you have said. For example, young males are likely to be negatively labelled by the police - use your textbook or the ONS website to find numerical evidence for that (e.g. they are more likely to be arrested or imprisoned than other social groups).
Once you are done, look at the flipside and any flaws that you can see in this theory. If you are discussing an individualist theory, such as Interactionism, you can always bring in structuralist views that consider society as a whole (e.g. Marxism, that says that individual can have no impact upon society).
ALWAYS remember to criticise the data - are the numbers that you used before right? Or are they shaped by the media, are they biased, are they a result of an under-reporting?
Remember that all of the above has been already said by some researcher.When you talk about labelling, mention Becker who came up with this theory. When you use statistics, try to memorise a publisher and a year when the data has been released. If you struggle to remember the exact year in the exam, just say 'a sociologist' - although, do try to memorise some names.
In conclusion, assess the theory you have been talking about in terms of validity, reliability, representativeness and ethics. Interactionism, for example, is good for talking about ethical issues - how the research was carried out? Did the researcher 'spy' after a drug dealer? Is it fair on the drug dealer, and should the researcher report the observed crime to the police?
Finish off with a very brief summary of what you have said.
Writing should take you between 45 minutes and an hour.
This is a general answer framework - you are welcome to ask any specific questions about theories or statistics! :)