It's important to demonstrate, particularly at foundation level, your ability to draw from observation, not solely from photographs. This could be life drawing, portraiture, landscapes or architectural structures. This is less pertinent at undergraduate or postgraduate, where your portfolio should ideally be more concise and relevant to your chosen subject area. Nonetheless, drawing is often considered the basis of art and design practice, and is therefore encouraged to be included where applicable. To clarify, what you include does not necessarily need to be finished drawings (unless you're applying for a specialist drawing or illustration related course), it need only be drawings in your sketchbook that helped to sustain and inform your final outcome (which doesn't need to involve drawing, it could be a photograph or a model).
The course team will likely be looking for the development of your ideas and areas of interest. This is usually and typically best shown in the form of a sketchbook. The course team will often place an emphasis on your ability to initiate, develop and even deviate throughout your work. This will give them the opportunity to understand your ethic and mindset, both as a creative and as a potential student on their course. For foundation level, your sketchbook should demonstrate your interest in, and exploration of, a range of different media and creative disciplines. For undergraduate and particularly postgraduate level, the development of your ideas should be more focused, and won't necessarily be in sketchbook form. With the increasing use of the digital medium, many artists and designers are, for example, preferring to document their work through the use of an online blog.
It's also encouraged to present a personal inquiry into any artists and designers, both past and present, that you like the work of. In addition, any agencies/studios, exhibitions, seminars or publications that you have taken an interest in. This is best presented in your sketchbook.
Applicants often overlook how their portfolio will be displayed, even though this is arguably one of the most important aspects to consider when preparing. There isn't a set approach to display your artwork, but there are suggested methods that can be employed.
Firstly, the size of your portfolio should be a maximum of A1 to a minimum of A3. From my own experience, I find A3 is the most ideal (both in education and beyond). A1 is more appropriate for fine art, where large canvases, for example, will need to be photographed. A3 marks the perfect balance because you can sufficiently display your artwork effectively, while making it easier to transport. The portfolio case can be anything you like, the most typical being a spine-mounted leather case (usually found in all good art retailers). An alternative would be a aluminum case of the same kind.
I would advise placing your most recent work first, and to ensure that labeling is not obstructive and easily readable, placing it ideally on the back of each piece of artwork (preferably in the far corner). If you're intending to display your sketchbook work, in addition to your finished artwork, it's important to arrange your work so that the course team can easily follow and understand how you developed an idea from the initial research to the finished artwork. Make sure to only include your best work, quality over quantity. Any large and heavy three-dimensional work should be photographed accordingly and displayed within your portfolio.