First, this is not a step by step tutorial carefully adjusted for specific versions of OS, Matlab, or EEGLAB. It is more of a generic guide, which may or may not work depending on your MATLAB or EEGLAB versions.
If you are using Windows things are straightforward:
If you are using MAC things are less straightforward. The MEX file that is downloaded when you follow the steps above is not compatible with OS (you will get an error saying so). Your alternative is to download the source code for the plugin, compile it (so that it creates the MEX file for your OS X), and put the folder including the compiled binary files in the plugins folder under EEGLAB. I couldn't get this to work because now not only did I need to deal with compatibility issues among OS, Matlab, EEGLAB and the importer package but as it turns out Xcode has changed some crucial stuff in the compiler recently (something to the with using "-o" instead of "-output" in the source file) and you have to find these instances and replace them. I didn't have any patience to do this. So I ended up setting up Matlab in Windows (in Parallels) and followed the steps above.
Once you import your data and can scroll through your data in EEGLAB and see the triggers, you have to set the channel locations. This is not very straightforward as well since EEGLAB does not come with the channel location files for the Waveguard caps. You can get the standard channel location files from your ASA installation. If you have a specific montage that you have used then you need to create the channel locations files for that montage. Got to ASA and Data -> Write -> Electrodes . If you run into any problems in using this file (due to your EEGLAB version - see discussion entries below) then you will need to use a converter script someone from Ant-Neuro wrote to import the channel locations as an array structure in the MATLAB environment (CHANLOCS) and set the Eeeglab channel location structure to the one created by the script (EEG.chanlocs = CHANLOCS). I have included all the files you need for channel locations in the zipped package below. You should also take a look at the discussions linked below before you start. Good luck.
Helpful EEGLAB listserv entries:
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