How to get better at Attention to Detail - ie reading the question properly

I have worked through some past papers and find that my biggest problem is making silly errors in answering the question because I miss little details or mis-read something. For example if you had a table of data with say Annual and Daily Widgets and you had to say get an average of the Daily column I would get an average of the Annual column - maybe just that is the first column I saw and assumed that is what was asked.
These are practice questions so I am not really stressed, but possibly just a little stressed to get thru the exam in the designated time. I wonder if stress is a factor. Do I need to try to calm myself down more when doing the exam?
Is it possible to practice for attention to detail? Any practice you can do?
How do you improve on Attention To Detail deficits in your own exam taking?