One key issue to think about should be your tent. What sort of condition is it in and are you confident that you can get it erected pretty quickly? If you're uncertain about anything then it's best to try and resolve the problem before you set off. It's often a good idea, for instance, to try putting your tent up in your garden a few days before leaving on the trip. By doing so, you should be able to identify whether you are likely to encounter any problems.
If there are going to be any problems then you'll be glad to find out about them in the setting of your own garden, rather than finding yourself in a state of panic as you try to put the tent up in potentially wet conditions on a campsite.Have you thought about food and drink? You may be thinking about eating out during your trip, in which case it's worth locating the site on a map and checking that it's close to some restaurants or pubs.
You may, alternatively, be planning to take your own food and drink with you. If this is the case then remember to draw up a list so that you know what you need to buy and what you need to pack. If you're intending to cook then you don't want to forget your camping stove and any pans that you may need.