Take the AWS CWI seminar. They will provide everything except the code you will be using for the open book examination.
As for the open book portion of the examination, I have always advocated the candidate should take the examination that is most closely related to the work he or she does. In other words, if the individual is inspecting structural steel, why take the examination with API 1104? If you are working as a pipe inspector in a process plant where the welding is per B31.3, why take the AWS D1.1 examination?
I have seen several instances where prospective employers have asked the candidate what examination was used when they passed their CWI examination. The candidate was rejected in favor for someone that took the CWI examination with a code that was more relevant to the type of inspections the candidate will perform. A number of DOT’s require the examination be passed with either D1.1 or D1.5 because they are the codes relevant to the work the inspector will be inspecting.
While AWS may not differentiate between the different codes used for the open book portion of the CWI examinations, many employers do. Consider carefully which open book examination is relevant to the industry you expect to work in.
Best regards - Al