You don't need any special equipment to take part in orienteering - choose your clothes according to whether you expect to walk, jog or run.
- You should always wear full leg cover, unless you know you will be orienteering on streets. Tracksuit bottoms will do, the lighter the better, or any old clothes. Jeans are not a good idea, as if it is wet they hold water and take a long time to dry.
- A T-shirt is fine for the upper body is the weather is fine; though you may want to consider long sleeves and/or extra light layer if it is colder
- For footwear - running shoes are best; but any shoes with a good grip will do.
Remember, that what you wear might well get dirty and/or wet - so you might want to consider some clean clothes to change into after your run. Don't forget the spare shoes and socks. Orienteering courses often have some quite muddy bits in them.
Extras you might like to consider are waterproofs, a woolly hat and gloves if you think you might get cold.