A very simple question but not to be underrated. The secret to a successfully designed site is to have a clear idea of what you are using your site for and whom you aim to attract through your pages. Your site may be used as an information guide, an extension of your business advertising, a forum or perhaps an online shop?
On deciding these two points, it should be easier to know what you will
need to give us in the way of text, pictures, imagery etc. Continuously
put yourself in the position of the viewer, ask yourself what they would
need to see to understand what you have to offer.
If your company has a logo and colour theme it is advisable to continue
this in the site.
This way the visitor (if familiar with you) is in no doubt that they are
at the right site.
If you still feel baffled, take some time browsing the web, look at the way your associates/competitors put the information across. Being a viewer it will become clearer which ways work better and therefore constructively doing their job. Remember some sites are to inform, some to sell!