There's no question that PowerPoint can brighten up a presentation. Instead of plain text, any of us, whatever the situation, can make our presentations much brighter and more engaging than ever - and we can't hope to make any kind of impact if we don't have the audience's full attention. Clearly, a presentation without any colour isn't going to be terribly effective.

But we can't just go slathering reds and greens and mauves and teals at random. There are pitfalls to the use of colours in your presentation, as well as benefits. Let's say that you're on the board of an insurance provider, and after some economic trouble, a presentation is being given on downsizing plans. There are troublesome projections for the future, calls for redundancies to be made, and a whole lot of bad news in general.

The glum and foreboding presentation, meanwhile, is coloured mostly in bright yellow and a shade of turquoise that would charm any toddler. It's not a particularly inspiring image, is it? And however important the content of the presentation, the colour scheme will seem ridiculous, and the presentation itself will be looked upon in much the same light. After all, whether we intend it or not every one of us is susceptible to making instinctive judgements based upon appearance - a presentation that looks silly will be taken that way.

So, what should we look for when picking out the appropriate colour scheme for our PowerPoint presentation?

Well, firstly, does the company have its own colours, that you might want to include? Of course, this might not always be relevant - there may not be a company involved, or there may be no reason to include a unique colour scheme - but it's important to be aware of when a presentation ought to be branded with a corporate identity, and how best to go about it.

Let's look at Michelle, whose presentation is promoting a tender for a constructor, hoping to win the council contract to build a new sporting complex on the edge of town. Her presentation has to be a positive one, and by introducing the company's colours (sky blue and white) to the pages, she can create a subconscious connection between the proposals and the benefits they bring, and the constructor.

However, there's a limit to how much she should use: a subtle hint (perhaps a sky blue and white stripe at the top and bottom of a slide, or a slim sky blue border around white areas) would be ideal, and can be coupled with an unobtrusive company logo; on the other hand, to colour everything with those two colours can be obtrusive and distracting, not to mention making the slides considerably less clear, negating the impact of using the brand colours in the first place.

Even if corporate identity isn't an issue, it's still essential to think about the colours. Remember the ridiculous insurance company presentation on redundancies? Of course, sensible colours, greys and blacks and deep blues and whites would have been more appropriate. But what if the presentation had been a lesson for young children? As long as the colours used are clear, there's no reason not to make them bright and upbeat enough to keep the children focused and entertained.

Every situation has its own demands - for instance, the insurance company might want to use more positive, bold colours (or corporate branding) when reporting something more optimistic - and the aim should always be to match your presentation's colour scheme with both the content and the audience. The colours are just a tool, an assistant that can improve the connection with your audience; they should never be the show themselves, but adapted to enhance that content and engage with that audience.

Microsoft PowerPoint can, of course, support any colour scheme you choose, and apply it throughout your presentation. But with such flexibility, you have to be cautious, careful not to head down the wrong route.

Be sure that you know your audience, where they are coming from and what they'll be expecting, and don't be afraid to experiment when you're putting the work together to find just the right style. It's also a good idea to consider a short training course, to get the very most out of everything that PowerPoint can do for you, with regard both to colour use and to everything else it can offer to make your presentation as effective as can be. And knowing how to use colours - the right colours - to enhance any presentation can help to make any message clear and successful, rather than miring it in shades of grey.