What to include and not in a portfolio? In the end it's up to you to represent yourself. But it always surprised me how many people do it pretty badly. If the kind of course you are applying for involves the kind of work that is not already in your portfolio you need to show for sure that you are interested and capable of doing it. So doing a personal project, which explores your interests, can help to explain your thinking and aspirations. If you think "I work full time in a bank and can't do special projects" then you obviously don't really want to go on that course enough. You have to show commitment.
Portfolios can take many forms: CDs, websites, flat presentation work, video and many other formats. Sketchbooks can be useful if they add something to the work being shown but are not essential. If you do submit them, mark up relevant/interesting pages. There is nothing more dull than a sketchbook full of shopping lists in a foreign language. Or endless sketch drawings of pigs. Yeah, they are good drawings but not really relevant.
Slides are good for fine art portfolios but for design not good at all. Slides (unless they are specifically asked for) of websites or flat work are useless. Why do people do this? If it's a website give the URL or put it on CD.
Copyright Rory Hamilton 2005 
The important thing in any portfolio is that it is clear to look at: i.e. with flat work put your best work first (chronological isn't always good). And don't put in 20 mediocre projects if 5, well presented good ones, will do. With CDs etc, make sure they are easy to navigate and be clear whether they are Mac or PC.
DVD (it used to be VHS) is always a great thing to send, as it just plays, no fuss. Objects are good too so long as you don't mind them getting lost/broken as can happen.
In applying for a job, research the employer, see what would most interest them in your portfolio and put that first. Again don't overload it. In the interview have stuff to show them that you haven't already sent.
The main thing is to let your portfolio convey your
enthusiasm, and professionalism and don't let it get boring.
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